Product description Product Name：Lightweight cycling helmet Product Material：EPS Foam + PC Shell EPS Head circumference(cm)：M(54-58cm)L(58-61cm) Helmet air holes：18 Product colours：Green Blue Red Product weight: (g)M(240G)L(245G) Product Features：Embedded,adjustable head circumference,removableLined,lightweight and breathable,no burden 1. Knob-type adjustment system: adjust the tightness as needed, fit the head more safely (suitable for most people's head circumference) 360° rotation to adjust the head circumference, counterclockwise to increase the head circumference, clockwise to reduce the head circumference. 2. Lightweight and comfortable to reduce the burden: high-quality lightweight EPS, reduce the burden on the neck during riding. 3. Comfortable lining: sweat-absorbent and antibacterial lining, fast perspiration, keep dry and impact-resistant, better protect your safety. 4. Round buckle: round buckle is firm and tight, simple, convenient and easy to operate, and quick to wear. 5. Thickened chin pad is removable and washable: thickened chin pad, with good sweat absorption ability, removable and more hygienic.