A. Features 1. It is relatively simple to install and disassemble, providing more convenient use. 2. This power assist sensor can help extend the cycling mileage with relatively high precision. 3. It can help prolong the battery service life, increase the vehicle's cruising range, and reduce the risk of damage to the battery caused by high - current discharge. 4. This product is suitable for bicycles, electric bicycles, etc. It can recognize power according to the pedaling speed, making pedaling during the cycling process easier and more energy - efficient. B. Specifications 1. Dimensions: The outer circle diameter is about 6.5 cm, and the inner circle diameter is about 1.5 cm. C. Package Contents 1. One electric bicycle power assist sensor. D. Notes 1. Due to different display settings and lighting effects, the actual color of the product may vary slightly from the color in the picture. 2. Since the measurements are done manually, an error of about 1 - 3 cm is allowed. (1 inch = 2.54 cm) Thank you for your support!