This helmet is perfect for use with recreational vehicles such as go karts, ATVs, or mini bikes. They are new helmets of discontinued models, and are not rated for racing or highway. Brand: Vector Sports Inc. Style: Open Face / Shorty Standard Made in the USA Shell: Polycarbonate Liner: Expandable Bead Polystrene Color: Black Guide for Helmet Size ***This is a generic guide, exact dimension for in stock helmets may vary slightly *** MEDIUM = 7 (Hat size) / 22.0" To obtain your correct helmet size, use a measuring tape across the forehead, around sides and back of head.BMI Karts