InMold unibody technology high quality PC shell EPS foam provides shockabsorbingmaking the helmet safer and more durable Head Size Easytouse dial fits different head sizes adjustable side straps to assist with a proper fit 50cm 57cm 197224Weight Approx 250g055lb VENTILATION 16 air flow channelsdetachable visor is easy to remove and installclassical streamlined design in frontextended rear coverage adds durability and extra protection Warning Tail Light on the back3 modesSteady FlashSlow FlashFast Flash Bring More Comfortable and Safety for your outdoor sports experience Rush tier strap system soft inner pads chin straps and chin pad with triangle regulatorshighimpact bucklequick connectdisconnect and equiped with a drawstring bag COMPLIANCEComplies with US Consumer Product Safety Commission Safety Standard for Bicycle Helmets for Persons Age 5 and Older