The Femto USB Drive Rear is very compact and lightweight. It is USB rechargeable with a durable molded construction. This construction has a waterproof rating of IPX7. This means that the LED is waterproof when immersed one meter deep and not longer than thirty minutes. The included strap can be mounted in different ways. The five output modes offer up to 5 lumens and the custom optics lens provides over 180° visibility. The Femto USB Rear can run for up to 15 hours and is easily rechargeable with the included micro-USB cable. A secure, threaded composite matrix cover, keeps the USB port clean and sealed. The Femto USB is perfect for serious cyclists looking for a simple and inexpensive way to add visibility. Also available as a pair.
The diagram below shows how many lumens the lamp offers in a given mode and how long the LED can sustain this. One lumen is equivalent to the light of a candle.

Specifications

Included accessories