A lightweight, Mips-equipped road bike helmet featuring 14 ventilation holes and a dedicated sunglass storage slot for comfortable rides. 14 ventilation holes provide airflow to help keep you cool on long rides; Lightweight construction: 300 g in size M and 330 g in size L; Mips technology helps reduce rotational motion in certain angled impacts; Dedicated sunglass storage slot keeps your sunglasses secure and within reach. Compatibility All Velotric Ebike Models. Choose the correct helmet size for your head circumference: M (55–58 cm) or L (58–61 cm). Notice Measure your head and choose the correct size before use. Adjust the dial fit system and chin strap so the helmet sits level and snug. Always wear the helmet properly fastened while riding.