Arkay Windows Limited

Company Summary:

Arkay Windows has been a trade manufacturer for over 40 years. We offer an extensive range of aluminium and UPVC products made to the highest standard with our advanced manufacturing machinery, all across England.

Contact:

Arkay Windows Limited
  • 573-575, Lordship Lane
  • Wood Green
  • London
  • N22 5LE

Fabricators For:

Regions Serviced:

  • United Kingdom

Products & Services:

    Doors

  • 58BD Doorsets

      Description:

      Single and Double Leaf, Inward and Outward Opening, Glazed with Midrail, Classified as "D"

      Approved Standard:
          Certified to: PAS 24:2016
          • Enhanced security performance requirements for doorsets and windows in the UK. Doorsets and windows intended to offer a level of security suitable for dwellings and other buildings exposed to comparable risk
          • Compliance Note: Certification held with Exova BMTrada cert 050/209 refers
      • Types:
        • Classified as "D", Double Leaf, External, Fully Glazed, Key/Key operation, No Letterplate Allowed, Outward Opening, Single Leaf, Thumb-turn release
      • Material:
        • Aluminium
  • 58BD+ Doorsets

      Description:

      Double and Single Leaf, Inward and Outward Opening, Glazed with Midrail, Classified as"D"

      Approved Standard:
          Certified to: PAS 24:2016
          • Enhanced security performance requirements for doorsets and windows in the UK. Doorsets and windows intended to offer a level of security suitable for dwellings and other buildings exposed to comparable risk
          • Compliance Note: Certifcation held with Exova BMTrada cert 050/209 refers
      • Types:
        • Classified as "D", Communal, Double Leaf, External, Fully Glazed, Key/Key operation, No Letterplate Allowed, Outward Opening, Single Leaf, Thumb-turn release
      • Material:
        • Aluminium
  • ADS 65 HD Single Acting Doorset Range

      Description:

      Single and Double Leaf Doorsets, Outward and Inward Opening, Thermally broken, Glazed, Classified as D

      Approved Standard:
          Certified to: PAS 24:2016
          • Enhanced security performance requirements for doorsets and windows in the UK. Doorsets and windows intended to offer a level of security suitable for dwellings and other buildings exposed to comparable risk
          • Compliance Note: Certifcation held with Exova BMTrada cert 050/209 refers
      • Types:
        • Classified as "D", Double Leaf, External, Fully Glazed, Inward Opening, Key/Key operation, No Letterplate Allowed, Outward Opening, Single Leaf, Thermally broken, Thumb-turn release
      • Material:
        • Aluminium
  • ADS 70 HD Single Acting Doorset Range

      Description:

      Single and Double Leaf Doorset, Outward and Inward Opening, Thermally Broken, Classified as D

      Approved Standard:
          Certified to: PAS 24:2016
          • Enhanced security performance requirements for doorsets and windows in the UK. Doorsets and windows intended to offer a level of security suitable for dwellings and other buildings exposed to comparable risk
          • Compliance Note: Certifcation held with Exova BMTrada cert 050/209 refers
      • Types:
        • Classified as "D", Double Leaf, External, Fully Glazed, Inward Opening, Key/Key operation, No Letterplate Allowed, Outward Opening, Single Leaf, Thermally broken, Thumb-turn release
      • Material:
        • Aluminium
  • ADS 75 HD HI Single Acting Doorset Range

      Description:

      Single and Doble Leaf Doorset, Outward and Inwards Opening, Thermally Broken, Glazed, Classified as D

      Approved Standard:
          Certified to: PAS 24:2016
          • Enhanced security performance requirements for doorsets and windows in the UK. Doorsets and windows intended to offer a level of security suitable for dwellings and other buildings exposed to comparable risk
          • Compliance Note: Certifcation held with Exova BMTrada cert 050/209 refers
      • Types:
        • Classified as "D", Double Leaf, External, Fully Glazed, Inward Opening, Key/Key operation, No Letterplate Allowed, Outward Opening, Single Leaf, Thermally broken, Thumb-turn release
      • Material:
        • Aluminium
  • BSF70 Doorset

      Description:

      Outward Opening, bi-folding, Sliding Folding, Mutli-leaf, Glazed, Low Threshold, Classified as D

      Approved Standard:
          Certified to: PAS 24:2016
          • Enhanced security performance requirements for doorsets and windows in the UK. Doorsets and windows intended to offer a level of security suitable for dwellings and other buildings exposed to comparable risk
          • Compliance Note: Certifcation held with Exova BMTrada cert 050/209 refers
      • Types:
        • Classified as "D", External, Folding-sliding and bi-folding doors, Fully Glazed, Low Threshold, No Letterplate Allowed, Outward Opening, Thumb-turn release
      • Material:
        • Aluminium
  • CP130 Lift and Slide Patio Doorset

      Description:

      Multileaf, Fully Glazed, Classified as D

      Approved Standard:
          Certified to: PAS 24:2016
          • Enhanced security performance requirements for doorsets and windows in the UK. Doorsets and windows intended to offer a level of security suitable for dwellings and other buildings exposed to comparable risk
          • Compliance Note: Certifcation held with Exova BMTrada cert 050/209 refers
      • Types:
        • Classified as "D", External, Fully Glazed, Inline-sliding and patio doors, Key/Key operation, Low Threshold, No Letterplate Allowed, Thumb-turn release
      • Material:
        • Aluminium
  • CP155 In Line Slide Patio Doorset

      Description:

      In Line Slide, Multileaf, Fully Glazed, Classified as D

      Approved Standard:
          Certified to: PAS 24:2016
          • Enhanced security performance requirements for doorsets and windows in the UK. Doorsets and windows intended to offer a level of security suitable for dwellings and other buildings exposed to comparable risk
          • Compliance Note: Certifcation held with Exova BMTrada cert 050/209 refers
      • Types:
        • Classified as "D", External, Fully Glazed, Inline-sliding and patio doors, Key/Key operation, Low Threshold, No Letterplate Allowed, Thumb-turn release
      • Material:
        • Aluminium
  • CP155 Lift and Slide Patio Doorset

      Description:

      Multileaf, Fully Glazed, Classified as D

      Approved Standard:
          Certified to: PAS 24:2016
          • Enhanced security performance requirements for doorsets and windows in the UK. Doorsets and windows intended to offer a level of security suitable for dwellings and other buildings exposed to comparable risk
          • Compliance Note: Certifcation held with Exova BMTrada cert 050/209 refers
      • Types:
        • Classified as "D", External, Fully Glazed, Inline-sliding and patio doors, Key/Key operation, Low Threshold, No Letterplate Allowed, Thumb-turn release
      • Material:
        • Aluminium
  • Concept Series Doorset

      Description:

      Double and Single Leaf doorsets, Inward and Outward Opening, Glazed, Classified as D

      Approved Standard:
          Certified to: PAS 24:2016
          • Enhanced security performance requirements for doorsets and windows in the UK. Doorsets and windows intended to offer a level of security suitable for dwellings and other buildings exposed to comparable risk
          • Compliance Note: Certifcation held with Exova BMTrada cert 050/209 refers
      • Types:
        • Classified as "D", Double Leaf, External, Fully Glazed, Inward Opening, Key/Key operation, No Letterplate Allowed, Outward Opening, Single Leaf, Thumb-turn release
      • Material:
        • Aluminium
  • ECO 50 & 70 Doorset Range

      Description:

      Single and Double Leaf, Inward and Outward Opening, Fully Glazed, Classified as"D"

      Approved Standard:
          Certified to: PAS 24:2016
          • Enhanced security performance requirements for doorsets and windows in the UK. Doorsets and windows intended to offer a level of security suitable for dwellings and other buildings exposed to comparable risk
          • Compliance Note: Certifcation held with Exova BMTrada cert 050/209 refers
      • Types:
        • Classified as "D", Communal, Double Leaf, External, Fully Glazed, Inward Opening, No Letterplate Allowed, Outward Opening, Single Leaf
      • Material:
        • Aluminium
  • GT55TB Electronic Access Doorset

      Description:

      Single or Double leaf, Dual Acting, Electronic Access, Fully Glazed, Classified as "D"

      Approved Standard:
          Certified to: PAS 24:2016
          • Enhanced security performance requirements for doorsets and windows in the UK. Doorsets and windows intended to offer a level of security suitable for dwellings and other buildings exposed to comparable risk
          • Compliance Note: Certifcation held with Exova BMTrada cert 050/209 refers
      • Types:
        • Classified as "D", Communal, Double Leaf, External, Fully Glazed, Inward Opening, Key/Key operation, No Letterplate Allowed, Outward Opening, Single Leaf, Thumb-turn release
      • Material:
        • Aluminium
  • GT55TB Face Fix Panic Exit Doorset

      Description:

      Double and Single Leaf, Outward Opening, emergency egress release, Classified as "D"

      Approved Standard:
          Certified to: PAS 24:2016
          • Enhanced security performance requirements for doorsets and windows in the UK. Doorsets and windows intended to offer a level of security suitable for dwellings and other buildings exposed to comparable risk
          • Compliance Note: Certifcation held with Exova BMTrada cert 050/209 refers
      • Types:
        • Classified as "D", Double Leaf, Emergency Egress Release, Fully Glazed, Outward Opening, Secure Emergency Exit Doors, Single Leaf
      • Material:
        • Aluminium
  • GT55TB Multipoint Locking Doorset

      Description:

      Single or Double leaf, Pivot hinged, Outward Opening, Fully Glazed, Classified as "D"

      Approved Standard:
          Certified to: PAS 24:2016
          • Enhanced security performance requirements for doorsets and windows in the UK. Doorsets and windows intended to offer a level of security suitable for dwellings and other buildings exposed to comparable risk
          • Compliance Note: Certifcation held with Exova BMTrada cert 050/209 refers
      • Types:
        • Classified as "D", Communal, External, Fully Glazed, Inward Opening, Key/Key operation, No Letterplate Allowed, Outward Opening, Pivot, Single Leaf, Thumb-turn release
      • Material:
        • Aluminium
  • GT55TB Panic Exit Doorset

      Description:

      Single Leaf, Pivot Hinged, Outward Opening, Fully Glazed, Multi-point Locking, Classified as "D"

      Approved Standard:
          Certified to: PAS 24:2016
          • Enhanced security performance requirements for doorsets and windows in the UK. Doorsets and windows intended to offer a level of security suitable for dwellings and other buildings exposed to comparable risk
          • Compliance Note: Certifcation held with Exova BMTrada cert 050/209 refers
      • Types:
        • Classified as "D", Communal, Emergency Egress Release, External, Fully Glazed, No Letterplate Allowed, Outward Opening, Pivot, Single Leaf, Thumb-turn release
      • Material:
        • Aluminium
  • Reynaers CF68 Sliding and Folding Doorset

      Description:

      Outward Opening Multi-leaf, Fully Glazed, Classified as "D"

      Approved Standard:
          Certified to: PAS 24:2016
          • Enhanced security performance requirements for doorsets and windows in the UK. Doorsets and windows intended to offer a level of security suitable for dwellings and other buildings exposed to comparable risk
          • Compliance Note: Certifcation held with Exova BMTrada cert 050/209 refers
      • Types:
        • Classified as "D", External, Folding-sliding and bi-folding doors, Fully Glazed, Key/Key operation, Outward Opening, Thumb-turn release
      • Material:
        • Aluminium
  • Reynaers CF77 Sliding and Folding Doorset

      Description:

      Outward Opening, Multi-leaf, Fully Glazed, Classified as "D"

      Approved Standard:
          Certified to: PAS 24:2016
          • Enhanced security performance requirements for doorsets and windows in the UK. Doorsets and windows intended to offer a level of security suitable for dwellings and other buildings exposed to comparable risk
          • Compliance Note: Certifcation held with Exova BMTrada cert 050/209 refers
      • Types:
        • Classified as "D", External, Folding-sliding and bi-folding doors, Fully Glazed, Key/Key operation, No Letterplate Allowed, Outward Opening, Thumb-turn release
      • Material:
        • Aluminium
  • Vision 50 Door Range

      Description:

      Double Leaf, Double Acting, Fully Glazed, Classified as "D"

      Approved Standard:
          Certified to: PAS 24:2016
          • Enhanced security performance requirements for doorsets and windows in the UK. Doorsets and windows intended to offer a level of security suitable for dwellings and other buildings exposed to comparable risk
          • Compliance Note: Certifcation held with Exova BMTrada cert 050/209 refers
      • Types:
        • Classified as "D", Communal, Double Leaf, External, Fully Glazed, Inward Opening, Key/Key operation, No Letterplate Allowed, Outward Opening, Thumb-turn release
      • Material:
        • Aluminium
  • Windows

  • AWS 50, AWS 50 SL Range

      Description:

      Inward Opening Tilt & Turn Casement Windows, Classified as W

      Approved Standard:
          Certified to: PAS 24:2016
          • Enhanced security performance requirements for doorsets and windows in the UK. Doorsets and windows intended to offer a level of security suitable for dwellings and other buildings exposed to comparable risk
          • Compliance Note: Certification held with Exova BMTrada cert 031/181 refers
      • Types:
        • Casement, Classified as "W", Inward Opening, Tilt and Turn
      • Material:
        • Aluminium
  • AWS 60 HI, AWS 60 SL HI Range

      Description:

      Inward Opening Tilt & Turn Casement Windows, Classifed as W

      Approved Standard:
          Certified to: PAS 24:2016
          • Enhanced security performance requirements for doorsets and windows in the UK. Doorsets and windows intended to offer a level of security suitable for dwellings and other buildings exposed to comparable risk
          • Compliance Note: Certification held with Exova BMTrada cert 031/181 refers
      • Types:
        • Casement, Classified as "W", Inward Opening, Tilt and Turn
      • Material:
        • Aluminium
  • AWS 60, AWS 60 SL Range

      Description:

      Inward Opening Tilt & Turn Casement Windows, Classifed as W

      Approved Standard:
          Certified to: PAS 24:2016
          • Enhanced security performance requirements for doorsets and windows in the UK. Doorsets and windows intended to offer a level of security suitable for dwellings and other buildings exposed to comparable risk
          • Compliance Note: Certification held with Exova BMTrada cert 031/181 refers
      • Types:
        • Casement, Classified as "W", Inward Opening, Tilt and Turn, WKT
      • Material:
        • Aluminium
  • AWS 60, AWS 60.HI Range

      Description:

      Outward Opening, Casement Windows, Top and Side Hung, Classified as W

      Approved Standard:
          Certified to: PAS 24:2016
          • Enhanced security performance requirements for doorsets and windows in the UK. Doorsets and windows intended to offer a level of security suitable for dwellings and other buildings exposed to comparable risk
          • Compliance Note: Certification held with Exova BMTrada cert 031/181 refers
      • Types:
        • Casement, Classified as "W", Outward Opening, Side-hung, Top-hung
      • Material:
        • Aluminium
  • AWS 65 BS Range

      Description:

      Inward Opening Tilt & Turn Casement Windows, Classfied as W

      Approved Standard:
          Certified to: PAS 24:2016
          • Enhanced security performance requirements for doorsets and windows in the UK. Doorsets and windows intended to offer a level of security suitable for dwellings and other buildings exposed to comparable risk
          • Compliance Note: Certification held with Exova BMTrada cert 031/181 refers
      • Types:
        • Casement, Classified as "W", Inward Opening, Tilt and Turn
      • Material:
        • Aluminium
  • AWS 65 Range

      Description:

      Outward Opening Casement Windows, Top and Side Hung, Classified as W

      Approved Standard:
          Certified to: PAS 24:2016
          • Enhanced security performance requirements for doorsets and windows in the UK. Doorsets and windows intended to offer a level of security suitable for dwellings and other buildings exposed to comparable risk
          • Compliance Note: Certification held with Exova BMTrada cert 031/181 refers
      • Types:
        • Casement, Classified as "W", Outward Opening, Side-hung, Top-hung
      • Material:
        • Aluminium
  • AWS 65, AWS 65 SL Range

      Description:

      Inward Opening Tilt & Turn Casement Windows, Clssified as W

      Approved Standard:
          Certified to: PAS 24:2016
          • Enhanced security performance requirements for doorsets and windows in the UK. Doorsets and windows intended to offer a level of security suitable for dwellings and other buildings exposed to comparable risk
          • Compliance Note: Certification held with Exova BMTrada cert 031/181 refers
      • Types:
        • Casement, Classified as "W", Inward Opening, Tilt and Turn
      • Material:
        • Aluminium
  • AWS 70 HI BS Range

      Description:

      Inward Opening Tilt & Turn Casement Windows, Classified as W

      Approved Standard:
          Certified to: PAS 24:2016
          • Enhanced security performance requirements for doorsets and windows in the UK. Doorsets and windows intended to offer a level of security suitable for dwellings and other buildings exposed to comparable risk
          • Compliance Note: Certification held with Exova BMTrada cert 031/181 refers
      • Types:
        • Casement, Classified as "W", Inward Opening, Tilt and Turn
      • Material:
        • Aluminium
  • AWS 70 HI Range

      Description:

      Outward Opening Casement Windows Top and Side Hung, Classified as W

      Approved Standard:
          Certified to: PAS 24:2016
          • Enhanced security performance requirements for doorsets and windows in the UK. Doorsets and windows intended to offer a level of security suitable for dwellings and other buildings exposed to comparable risk
          • Compliance Note: Certification held with Exova BMTrada cert 031/181 refers
      • Types:
        • Casement, Classified as "W", Outward Opening, Side-hung, Top-hung
      • Material:
        • Aluminium
  • AWS 70 HI, AWS 70 SL HI Range

      Description:

      Inward Opening Tilt & Turn Casement Windows, Classified as W

      Approved Standard:
          Certified to: PAS 24:2016
          • Enhanced security performance requirements for doorsets and windows in the UK. Doorsets and windows intended to offer a level of security suitable for dwellings and other buildings exposed to comparable risk
          • Compliance Note: Certification held with Exova BMTrada cert 031/181 refers
      • Types:
        • Casement, Classified as "W", Inward Opening, Tilt and Turn
      • Material:
        • Aluminium
  • AWS 75 BS SI+, AWS 75 WF SI+ Range

      Description:

      Inward Opening Tilt & Turn Casement Windows, Classified as W

      Approved Standard:
          Certified to: PAS 24:2016
          • Enhanced security performance requirements for doorsets and windows in the UK. Doorsets and windows intended to offer a level of security suitable for dwellings and other buildings exposed to comparable risk
          • Compliance Note: Certification held with Exova BMTrada cert 031/181 refers
      • Types:
        • Casement, Classified as "W", Inward Opening, Tilt and Turn
      • Material:
        • Aluminium
  • AWS 75 SI, AWS 75 SL SI Range

      Description:

      Inward Opening Tilt & Turn Casement Windows, Classified as W

      Approved Standard:
          Certified to: PAS 24:2016
          • Enhanced security performance requirements for doorsets and windows in the UK. Doorsets and windows intended to offer a level of security suitable for dwellings and other buildings exposed to comparable risk
          • Compliance Note: Certification held with Exova BMTrada cert 031/181 refers
      • Types:
        • Casement, Classified as "W", Inward Opening, Tilt and Turn
      • Material:
        • Aluminium
  • AWS 90 BS SI + Range

      Description:

      Inward Opening Tilt & Turn Casement Windows, Classified as W

      Approved Standard:
          Certified to: PAS 24:2016
          • Enhanced security performance requirements for doorsets and windows in the UK. Doorsets and windows intended to offer a level of security suitable for dwellings and other buildings exposed to comparable risk
          • Compliance Note: Certification held with Exova BMTrada cert 031/181 refers
      • Types:
        • Casement, Classified as "W", Inward Opening, Tilt and Turn
      • Material:
        • Aluminium
  • Aluk 58BW Window Range

      Description:

      Casement, Tilt & Turn, Top Swing Fully Reversible, Inward Opening ,Outward Opening, Top and Side Hung, Classified W,

      Approved Standard:
          Certified to: PAS 24:2016
          • Enhanced security performance requirements for doorsets and windows in the UK. Doorsets and windows intended to offer a level of security suitable for dwellings and other buildings exposed to comparable risk
          • Compliance Note: Certification held with Exova BMTrada cert 031/181 refers
      • Types:
        • Casement, Classified as "W", Fully Reversible, Inward Opening, Key operation, Outward Opening, Side-hung, Tilt and Turn, Top swing, Top-hung
      • Material:
        • Aluminium
  • Aluk 72BW Window Range

      Description:

      Outward Opening Casement, Inward Opening Tilt and Turn, Top and Side Hung, Classified as W

      Approved Standard:
          Certified to: PAS 24:2016
          • Enhanced security performance requirements for doorsets and windows in the UK. Doorsets and windows intended to offer a level of security suitable for dwellings and other buildings exposed to comparable risk
          • Compliance Note: Certification held with Exova BMTrada cert 031/181 refers
      • Types:
        • Casement, Classified as "W", Inward Opening, Outward Opening, Side-hung, Tilt and Turn, Top-hung
      • Material:
        • Aluminium
  • Aluk Casement Windows

      Description:

      Outward Opening, Top and Side Hung, Classified as W

      Approved Standard:
          Certified to: PAS 24:2016
          • Enhanced security performance requirements for doorsets and windows in the UK. Doorsets and windows intended to offer a level of security suitable for dwellings and other buildings exposed to comparable risk
          • Compliance Note: Certification held with Exova BMTrada cert 031/181 refers
      • Types:
        • Casement, Classified as "W", Side-hung, Top-hung
      • Material:
        • Aluminium
  • Concept Series CS38-SL

      Description:

      Top Hung Option ,Classified as W

      Approved Standard:
          Certified to: PAS 24:2016
          • Enhanced security performance requirements for doorsets and windows in the UK. Doorsets and windows intended to offer a level of security suitable for dwellings and other buildings exposed to comparable risk
          • Compliance Note: Certification held with Exova BMTrada cert 031/181 refers
      • Types:
        • Casement, Classified as "W", Top-hung
      • Material:
        • Aluminium
  • Concept Series CS68, CS77 and CS86

      Description:

      Outward Opening Casement, Classified as W

      Approved Standard:
          Certified to: PAS 24:2016
          • Enhanced security performance requirements for doorsets and windows in the UK. Doorsets and windows intended to offer a level of security suitable for dwellings and other buildings exposed to comparable risk
          • Compliance Note: Certification held with Exova BMTrada cert 031/181 refers
      • Types:
        • Casement, Classified as "W", Outward Opening
      • Material:
        • Aluminium
  • Concept Series Window

      Description:

      Parallel Outward Opening, Classifed as W

      Approved Standard:
          Certified to: PAS 24:2016
          • Enhanced security performance requirements for doorsets and windows in the UK. Doorsets and windows intended to offer a level of security suitable for dwellings and other buildings exposed to comparable risk
          • Compliance Note: Certification held with Exova BMTrada cert 031/181 refers
      • Types:
        • Casement, Classified as "W", Key operation, Outward Opening, Parallel opening
      • Material:
        • Aluminium
  • ECO 50 Window Range

      Description:

      Tilt & Turn, Inward Opening, W

      Approved Standard:
          Certified to: PAS 24:2016
          • Enhanced security performance requirements for doorsets and windows in the UK. Doorsets and windows intended to offer a level of security suitable for dwellings and other buildings exposed to comparable risk
          • Compliance Note: Certification held with Exova BMTrada cert 031/181 refers
      • Types:
        • Classified as "W", Key operation, Tilt and Turn
      • Material:
        • Aluminium
  • ECO window Range

      Description:

      Casement, Outward Opening, Classified as "W"

      Approved Standard:
          Certified to: PAS 24:2016
          • Enhanced security performance requirements for doorsets and windows in the UK. Doorsets and windows intended to offer a level of security suitable for dwellings and other buildings exposed to comparable risk
          • Compliance Note: Certification held with Exova BMTrada cert 031/181 refers
      • Types:
        • Casement, Classified as "W", Key operation, Outward Opening
      • Material:
        • Aluminium
  • Eclectic R9 Window Range

      Description:

      Casement, Outward opening, Classified as "W"

      Approved Standard:
          Certified to: PAS 24:2016
          • Enhanced security performance requirements for doorsets and windows in the UK. Doorsets and windows intended to offer a level of security suitable for dwellings and other buildings exposed to comparable risk
          • Compliance Note: Certification held with Exova BMTrada cert 031/181 refers
      • Types:
        • Casement, Outward Opening, Side-hung, WKT
      • Material:
        • PVC-U
  • SL38 Classic and Ferro Window Range

      Description:

      Tilt & Turn, Inward Opening, Classified as "W"

      Approved Standard:
          Certified to: PAS 24:2016
          • Enhanced security performance requirements for doorsets and windows in the UK. Doorsets and windows intended to offer a level of security suitable for dwellings and other buildings exposed to comparable risk
          • Compliance Note: Certification held with Exova BMTrada cert 031/181 refers
      • Types:
        • Classified as "W", Inward Opening, Key operation, Tilt and Turn
      • Material:
        • Aluminium