About the Femto Drive Rear Light The Lezyne Femto Drive Rear light is designed as an affordable yet brilliant compact \\\"be seen\\\" Commute / Road / MTB safety rear light. Engineered alloy body is light weight (31g with strap) and tough with long lasting, high polished and anodised finish. Five settings, including innovative \\\"orbing\\\" mode are controlled by pressing the actual lens which acts as a large and easy to use button even in winter gloves. New \\\"hipster\\\" easy-fit bracket with patented durable rubber strap fits the bike, your belt, clothing, bags, seatpack, just about anywhere you like. Improved side visibility custom frosted lens delivers 180 degrees beam visibility. Internal reflector boosts output. Easy entry battery replacement is fully water resistant (FL1 standard). Each Femto is supplied with 2x CR2032 (watch type) batteries. Replacement batteries available in twin pack and x8 pack. Lezyne offer a 2 year warranty. Output rating: Rear 7 lumens (red). Burn Times: Steady Modes 30hours, Flash Mode: 60 hours. Day or night. Ride safe, always be seen! Key Features > User Type: user can be seen > Brightness: 7 Lumens > Power Source: Battery - CR 2032 > Run Time:30h Constant - 60h Flashing > Mounting: Seatpost/Belt clip - Tool free > Light modes: 5 > Front/Rear/Set: Rear