Lezyne's Macro Drive Duo features a lightweight, sturdy CNC-machined aluminum body with an integrated rear light, making it the ultimate combo! Constant Lumens power management drives the LED at a bright 400 lumens for the front LED and 5 lumens for the rear LED, and the Intelligent Power Indicator button allows you to check the power level at any time. You're able to toggle to the rear light mode to choose your desired setting. The Side Visibility Cuts allow for 180 degrees of visibility. The Li-ion battery (non-replaceable) is recharged by a fast, high effciency 2-amp wall adaptor, or via a Micro USB cable for ultimate convenience. The Rear LED back cap conceals the USB port for recharging the battery. This unobstrusive light is designed for helmet mounts and comes with Lezyne's Composite Matrix Helmet Mount.