12 Holes Smart Bike Helmet Adjustable Head Circumference Cycling Sports Protective Gear with Front Lighting and Back Warning Light

Main Features:
1. Impact-resistant integrated PC shell, wear-resistant, fall-resistant, and higher safety factor
2. 12 holes for heat dissipation and ventilation, which are convenient for exhausting the heat and moisture in the helmet
3. Adjustable head circumference, you can adjust the helmet according to your head size
4. 750mAh battery capacity, can last 10h
5. The design of front lighting and back warning lights makes night riding safer
S: 48-53cm head circumference
M: 54-57cm head circumference
L: 58-61cm head circumference