Product size about : 4*4*2.8cm / 1.56"*1.56"*1.09" Product color: As shown in the figure Product material:ABS product features: 1.This smart bike tail light features a cute heart-shaped design that adds style to your ride while keeping you visible with its bright red light. 2.It automatically turns on when it senses vibration or braking, so you never have to worry about forgetting to switch it on manually. 3.Choose from four light modessteady, slow flash, fast flash, or breathing flashto match your riding style and conditions. 4.With a long-lasting battery that works for up to 26 hours and stays charged for over 3 months on standby, its perfect for daily rides and long adventures. 5.Built to be waterproof and tough, this lightweight light is easy to install and fits securely on your bike seat or frame. Precautions: 1. As we all know , the different computers display colors differently, the color of the actual item may vary slightly from the following images. 2. If you feel difficult to choose the size, you can contact us at any time. We will give you some suggestions, but for your reference only. Shipment includes: 1 pc taillight