509 Altitude Triangle Helmet
  • 509 Altitude Triangle Helmet - Matte Blue
  • 509 Altitude Triangle Helmet - Matte Blue

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509 Altitude Triangle Helmet

The 509 Altitude Helmet is a sleek yet aggressive helmet.


  • Thermoplastic poly alloy outer shell
  • Intermediate oval
  • Innovative dual density interlocking EPS foam liner
  • Front chin protection from specially designed expanded polyurethane chin insert
  • 8 intake/exhaust vent ports
  • Cold weather breath box included
  • 4 shell sizes
  • Removable and washable premium liner
  • Neck brace ready
  • Class-leading eyeport opening dimensions for optimal peripheral vision
  • Perfect 509 goggle fit
  • One-piece eyeport trim
  • Integrated front mouth vent
  • Innovative universal camera mount that attaches to top visor in seconds
  • Meets or exceeds DOT and ECE safety certification standards
  • Helmets sized 2XL and larger use 509 XL goggles

509 Helmet Sizing

Size Head (cm)
XS 53-54
SM 55-56
MD 57-58
LG 59-60
XL 61-62
2XL 63-64
3XL 64-65
4XL 66-67

Sizing information is provided by the manufacturer and does not guarantee a perfect fit.

How To Measure

H Head Wrap a cloth measuring tape around your head just above your eyebrows and ears. Pull the tape comfortably snug, read the length, repeat for good measure and use the largest measurement.
Product Style RevZilla Item # Manufacturer Product # Availability
Matte Blue / 2XL 1146769 509HELABT2XL Out of Stock
Matte Blue / 3XL 1146770 509HELABT3XL Out of Stock
Matte Blue / 4XL 1146771 509HELABT4XL Out of Stock
Matte Blue / LG 1146767 509HELABTLG Out of Stock
Matte Blue / MD 1146766 509HELABTMD Out of Stock
Matte Blue / SM 1146765 509HELABTSM Only 1 Left: Ships within 24 hours
Matte Blue / XL 1146768 509HELABTXL Out of Stock
Matte Blue / XS 1146764 509HELABTXS Out of Stock


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If your order arrives and it is not right, we will we'll fix it, NO NONSENSE, we promise.

Doesn't fit or just not happy with it? You can return any new, unused and unaltered item within 30 business days of delivery receipt of your item. We will issue a full refund to your original payment method.

See our full Return Policy for all of the pertinent details.

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