Alpinestars SM3 Radium Helmet — XS

Engineered for MX, enduro and off-road use, this helmet prioritizes ease of use, comfort and impact performance.

Shell construction uses a thermo-injected shell with a special polymer blend and variable thickness to balance impact protection with low weight.

A patented low-friction coating is applied to the inner EPS liner to reduce rotational acceleration from oblique impacts, mimicking the brain's natural cerebrospinal slip plane.

A patented visor release system ensures controlled visor detachment to reduce neck forces during an impact.

Maximized ventilation with 10 inlets and 7 exhaust ports supports efficient heat transfer and airflow.

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