The Lezyne femto duo evolved from the popular Femto series, the two in one safety light features a front & rear light coupled by a composite matrix junction that’s compatible with nearly all vented-style helmets. The LEDs are housed in a super compact, lightweight & durable machined aluminum body, & the high-grade polycarbonate lenses provide side visibility & double as the power button. The front emits 15 lumens, while the rear puts out 7 lumens; both feature three different output modes. With easy to replace CR2032 batteries, the Femto Duo is a simple front & rear lighting system for increased nighttime visibility.