The Lezyne Macro Drive Duo features a lightweight & sturdy CNC-machined aluminium body with an integrated rear light, making it the ultimate combo! Constant Lumens power management drives the LED at a bright 400 lm for the front LED & 5 lm for the rear LED, & the Intelligent Power Indicator button allows the user to check the power level at any time. Intelligently designed, the user is able to toggle to the rear light mode to choose their desired setting. The Side Visibility Cuts allow for 180 degrees of visibility, especially from the side. The Li-ion battery (non-replaceable) is recharged either with a fast, high e?ciency, 2 Amp charging with a compatible wall adaptor, or via a Micro USB (Universal Serial Bus) cable for ultimate convenience. The Rear LED back cap design conceals the USB (Universal Serial Bus) port for recharging the battery. This unobstrusive light is designed for helmet mounts & comes with Lezynes Composite Matrix Helmet Mount.