The GIRO Rodeo Blue Aviator Pigs Toddler Helmet Benefits and features Acu Dialfit system provides rock solid stability Built in visor for squint free rides Rear reflective sticker offers added visibility 6 top vents for better cooling Microshell with built in bug net CPSC approved Target User Ages 8 mths to 4 years Fits Head Size 18.75 20.5 NOTE To ensure a proper fit measure the circumference of the child's head by wrapping a measuring tape around their head just above the ears and level front to back. The age limit 8 mths to 4 years is approximated.