West Biking USB Rechargeable Waterproof Cycling Taillights Bike Bicycle Tail Light, Super Bright LED Headlight Easy Tool-Less Installation Fit All Bicycles, 4 Modes Design Fit all Bicycles: Easy Tool-Less Installation, Waterproof. Mount this bike rear light anywhere you want in seconds, such as the handlebar, the seat post or anywhere on the frame. Mount the rear bike light on the back of your helmet and you have yourself a bike helmet light. With the specially designed rubber band, the taillight can be securely installed onto frame tubes with various diameters, round or irregular USB Rechargeable: Fast Charging and Last long time. Super Bright LED. Four Modes Design: press the on/off button to change it. Comes with USB Cable and Rubber Band. Size:3 x 0.8 inches. the USB light can break through the darkness like a sharp edge. It is really stylish fitting on all kinds of bikes with its light-weighted, artistic design 100% Guaranty: If you aren't happy for ANY reason within 30 days, let us know and you get your money back!