S1 Lifer Brim Helmet From S1, a leader in helmet safety innovation for over 20 years. Built with specially formulated EPS Fusion Foam, the S1 Lifer protects against both low-force and high-force impacts — up to 5x more protective than non-certified soft foam helmets. Dual certified: ASTM F-1492-15 (skate/roller) + CPSC 16 CFR 1203 (bike/skate) EPS Fusion Foam for multi-impact protection Deep fit design for a secure, comfortable feel One size fits 20.5"- 23.25" Includes S, M, & L Pad Liners