ALPINESTARS SM3 Radium Helmet — XL, Red/White
MX, Enduro, and offroad helmet with a lightweight, multi-thickness shell, advanced ventilation, and an adjustable comfort fit.
Bank transfer
MX, Enduro, and offroad helmet with a lightweight, multi-thickness shell, advanced ventilation, and an adjustable comfort fit.
Built for MX, Enduro, and offroad riding, the SM3 Radium Helmet blends protection, comfort, and low weight in one focused design.
Its thermo-injected shell uses a polymer blend with varying thickness, while the lightweight outer shell is made from impact-resistant thermoplastic. A composite fiber inner shell sits between the outer shell and the EPS liner for added impact protection.
Fit is easy to tailor with the crown and cheek pads, and the helmet includes an Emergency Release System with removable cheek pads for safer removal. Venting is supported by ten inlets and seven exhaust ports, plus a visor designed to help direct air through the shell.
Comfort details include a recycled-material liner, hydration tube channels in the cheek pads, a 25 mm soft textile chin strap, and stainless steel D-rings for a secure fit.
| Features | Vented |
|---|---|
| Model | SM3 |
| Manufacturer part number | 8300726-3216-XL |
|---|
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