S1 Lifer Helmet is a certified high-impact skate helmet designed for roller skating, roller derby, ramps and outdoor use. Its close, secure fit is intended to stay stable while skating when sized correctly.Measure around the widest part of your head before ordering. A properly fitted helmet should feel snug and should not shift or bobble when you move your head. If you have a rounder head shape with more width at the sides, another helmet shape may fit better. Recommended head range for this Lifer model: approximately 20.5–23.5 inches Approximate liner sizes: XS 20.5 in, S 21 in, M 21.5 in, L 22 in, XL 22.5 in, 2XL 23 in, 3XL 23.5 in Use: Roller skating, roller derby, ramps and outdoor skating Fit: Snug, stable helmet fit when sized correctly Colors: Multiple matte, gloss, glitter and specialty finishes depending on availability For smaller or larger head measurements, consider the S1 Mini Lifer or Mega Lifer size range. Order the S1 Lifer Helmet online from Bo’s Boots on Wheels for shipping throughout the contiguous United States, or visit our San Diego skate shop for helmet sizing help.