MOON CPSC Safety Certified Adjustable Bike Helmet for Adult Men & Women and Teen Boys & Girls,with LED Lamp Light and Visor,Specialized for Cycling/Road Racing/MTB VENTILATION:21 flow vents allow air go in and out the bike helmet which help increase the speed and keep your ride cool. LIGHTWEIGHT AND CONVENENT: 275g super lightweight helmet will not cause any burden during your ride.A LED Rear Light added to provide you more convenience. FITS HEAD SIZES:(58-64cm)This road mountain bike helmet equipped with the easy-use dial system and side straps make it adjustable for different heads size and suitable for men and women (Unisex). REPLACEBLA BATTERIES:Battery life up to 12 months, easy to replace. When replace the battery, first you just need to a little force to open the safety light, and then unscrew the screw with a screwdriver can be replaced. IMPACT RESISTANCE&SAFETY:The helmet will successfully protect you.1.Made of a tough and durable PC, EPS foam through the In-Mold technology which help absorb the impact and protect the head during a crash;2.The inside liner will make you feel very comfortable, it will play a buffer role when your head is being impacted;3.The snap on/off visor made of PE for protection from sun and other pest elements;4.The insert buckle made of DuPont materials which cannot break easily to ensure your safety