Alpinestars SM3 Radium Helmet — L, Black

Designed for motocross, enduro and off‑road use, this helmet integrates innovations optimized for ease of use, all‑day comfort and reliable impact performance.

The thermo‑injected shell employs a special polymer blend with varying thicknesses to provide an optimal balance of impact protection and light weight.

A patented low‑friction coating applied to the inner EPS liner reduces rotational acceleration from oblique impacts by acting as a slip plane that mimics the brain's natural cerebrospinal fluid.

The visor release system is engineered to detach at a predetermined force to help reduce neck loads during an impact.

Ventilation is maximized via ten inlets and seven exhaust ports, promoting high heat transfer and rider comfort during intense activity.

Composition: acrylonitrile‑butadiene‑styrene 48%, polyurethane 20%, polystyrene (EPS) 16%, polypropylene 6%, polyvinyl chloride 4%, ethylene‑vinyl acetate 2%, steel 2%, expanded polypropylene 1%, polyamide 1%.