Alpinestars SM3 Radium Helmet — L, Matte gray

Engineered for MX, enduro and off-road use, the SM3 helmet features innovations optimized for ease of use, comfort and impact performance. 🪖

The shell is thermo-injected and built from a special polymer blend with varying thicknesses, engineered to deliver an optimal balance of impact protection and light weight.

A patented low-friction coating is applied to the inner surface of the main EPS liner to reduce rotational acceleration forces that can result from certain oblique impacts.

This low-friction layer acts as a slip plane to mimic the brain's own cerebrospinal fluid, the body's natural defence against oblique impacts.

A patented visor release system ensures the visor releases at a correct pre-determined force, effectively reducing forces on the neck during an impact.

Ventilation is maximised with high levels of heat transfer thanks to 10 inlets and 7 exhaust ports, keeping airflow consistent under load.

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