The trail beckons with the all-new A1 Drone Youth helmet from Troy Lee Designs. Ready to conquer any ride, the A1 leads the way with 16 large air vents and the innovative MIPS® system to go along with its EPS liner for outstanding impact protection. With all-mountain performance and safety in youth-specific shell size, the A1 goes where no youth mountain bike helmet has gone before. Key Features: Reinforced polycarbonate shell in-molded with the EPS liner extends down the sides and back of the head for maximum protection and durability, MIPS brain protection system reduces rotational forces to the brain, 8 pressurized intake passages draw in cool air for maximum ventilation, 8 rear vacuum vortex outlets help exhaust and draw heat from the head, Triple position adjustable retention system allows customized fit for various eyewear, head shape and riding styles, Single-piece, ultra-plush, removable and washable comfort liner made of anti-microbial moisture-wicking material for a dry, comfortable feel, Full-spectrum adjustable moto inspired visor with anodized aluminum hardware,Fits head size: 48 to 53cm.