Elevate your daily ride with the BASE CAMP cycling helmet. It's engineered for urban performance with sleek styling and thoughtful features like integrated sun visor, 9 cooling vents and detachable taillight, etc. gives commuters, e-bikers and everyday riders advanced head protection and cool rides. 1. The bike helmet with detachable LED light in 2 lighting modes: steady & flashing modes 2. Our bicycle helmet with LED taillight provides Max visibility and safety while riding on the city streets in the dark 3. Featuring 9 strategically placed vents, our bike helmet men keep you cool on longer rides 4. Simple Dial Fit System of the mens bike helmet lets you easily secure and adjust helmet fit with just one hand 5. Quick-release buckle of BASE CAMP bike helmet fastens effortlessly for a quick and secure fit 6. Soft, comfortable, moisture-wicking, and washable helmet pads 7. Integrated sun visor of the bike helmets for adults provides constant coverage against sun and rain 8. Our bike helmet for womens is dual safety certified for urban commuting, bike cycling, scooter riding 9. Soft padding under the chin-strap clasp prevents pinching or rubbing, ideal bike helmets for men and women 2 Lighting Modes Press one: turn it on steady mode Press two: trun it to flashing mode Press three: turn it off Technical Specs Material: EPS+PC, nylon Helmet weight: 0.62 lb Size: average size (Medium) Helmet circumference: 21.65-23.6 Inches/55-60 cm (It's recommended to people whose head circumference range of 21.65-23.25 inches to allow some tolerance for very long or thick hair) Package content 1 x Urban bike helmet 1 x Partable storage bag 1 x CR2032 battery 1 x User manual Please measure head circumference before order: Wrap a flexible tape measure around the largest portion of your head—about 1 in. above your eyebrows. Or, wrap a string or ribbon around your head, then measure the length of string with a straight-edge ruler or yardstick. The proper helmet fit is an important factor f