Bike tail light is designed for keeping you visible not only at night but also in the daytime while cycling, alerts drivers to your presence so they know to give you enough space. The bicycle rear light set can be easily installed and released without any tools. It can be attached virtually to any bike frame, fork, seat post, or handlebar, it also can be hung on your backpack, helmet, running gear or dog collar. Can be used as an emergency flashlight, keep it inside your car, basement, attic, and emergency kit. Use it when you're running, jogging, hiking, camping, walking your dog, cycling, changing a tire, night time family/kids activities, power outage and MORE! mount it under the saddle with a metal mounting bracket, or to the seat post with an adjustable silicone strap. Colour:Black Material:plastic Package Contents: 1 x bike tail light Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.