Bell's successful Formula Helmet provides incredible performance and value. With the addition of an integrated LED rear light, it's easy to see why the Formula LED is the clear choice. The included 20-lumen rear LED light aids riders in a safety boost thanks to increased visibility in low light riding conditions. Featuring a re-chargeable battery and included micro USB cable, the Formula LED checks all the boxes for safety, protection, and unique features. The Formula LED MIPS features the Multi-Directional Impact Protection System (MIPS) as standard equipment. MIPS technology reduces the rotational forces caused by angled impacts and this added technology does not compromise fit, ventilation, or style. Features: Fusion in-mold polycarbonate shell plus exposed polycarbonate roll cage delivers a lighter, more durable, and better ventilated design Multi-Directional Impact Protection System (MIPS) reduces the rotational forces caused by angled impacts Float Fit Race retention system is seamlessly integrated with MIPS and offers 3-way adjustability: height, pad width, and tension No-Twist Tri-Glides are quick-adjust fasteners to help keep straps flat and properly positioned Sweat Guide pad design pulls moisture away from brow pad and away from eyewear 19 vents USB Rechargeablle LED, Between 2.5 & 10 Hours of operation time; depending on mode. Size Guide: Small: 52-56cm, 20-22in Medium: 55-59cm, 21.6-23.2in Large: 58-62cm, 22.8-24.4in