1、PC and EPS: Premium EPS materials are used, and the density of foam is 75g/L. The thickened PC shell and the dual mode integrated molding technology make the helmet more compact, impact and vibration resistant, and protect your head. 2、Impact Resistant: The special shockproof system mimics the brain protection mechanism. The brain is surrounded by a layer of buffering cerebrospinal fluid, which can absorb gravity to protect the head when it is hit and shocked. When the impact occurs, the floating seismic layer cushions the impact force from different directions and angles, reducing the impact and vibration suffered by the brain, and avoiding more serious injuries due to spinal torsion. 3、Breathable: The bike helmet is designed with 11 air holes, which can divert air resistance, reduce wind resistance, ventilate, and reduce stuffiness 4、Adjustable Size: Thanks to its adjustable dial system and side straps, the bike helmet can accommodate heads of most sizes, with a custom fit and fit for men and women. Suggested head circumference is 58‑61cm. 5、Applicable Scenarios: This bike helmet is suitable for mountain cycling, road cycling, skiing, commuting, scooter riding, etc. Provide effective protection for you and your heads. Item Type: Bike Helmet Material: PC, EPS Gross Weight: 722g / 25.5oz Head Circumference: 58-61CM / 22.8-24.0in Number of Holes: 11 holes 1 x Bike Helmet 1 x Manual