【Adjustable Kids Helmet】 BURSUN kids bike helmet available in 2 sizes. Small: 18.90"-21.3" / 48-54 cm, suitable for 3-8 years old kids; Medium: 20.47"-22.83" / 52-58 cm, suitable for 8-14 years old youth. Please do remember to use a string and tape to measure your child’s head before you place the order.【High Quality Durable Material】 Our kids helmet is made of ABS and shock-absorbing EPS foam, Constitute multiple protection system, specially designed for multiple-sports head protection. Kids protective gear made of tough and durable PE shell with breathable Polyester lining, which could provide safety protection to kids knee elbow and wrist.【Breathable -Comfortable】 This kids bike helmet has a special adjustment dial system & adjustable straps to ensure your children achieve a perfect and safe fit. And 11 individual air vents that will keep your kids Cool & Comfortable for fun when playing..【Safe and Reliable】Complies with U.S. Consumer Product Safety Commission Safety Standard for Bicycle Helmets for Persons Age 1 and Older (Extended Head Coverage), this toddler bike helmet can provide professional protection to your children, make them play safely and happily..【What You Get】 Kids protective gear including 1 x bike Helmet, 2 x Elbow Pad, 2 x Knee Pad, 2 x Wrist Pad, please check the items clearly when you receive the package. If you have any questions about our kids bike helmet, please let us know, we will help you until the problem is solved.