Recommended for children ages 3-5, but will fit most heads measuring 48-52 cm. Always take a head measurement. Head sizes and shapes can vary, even within an age range. Using a helmet that doesn't fit can be dangerous. Complies with the U.S. CPSC Safety Standard for Bicycle Helmets for Persons Age 1 and Older (Extended Head Coverage). Also complies with U.S. ASTM Safety Standard for multi-impact Skateboard Helmets. 3D Skye ear and goggle details Hardshell construction Vents to keep little heads cool Easy to adjust chin strap Fit type: Universal Fit