Features: 1. Made of high quality materials, with fine workmanship and precise assembly. 2. Hall sensor has multiple advantages such as compact size, light weight, long durability, shockproof, anti-corrosion and dustproof, good for electric bicycle support. 3. 1:1 assist sensor is good for pedal assist electric bike drive system. Save your labor on pedaling. 4. Suitable for almost all electric bikes on the market. 5. Easy to install and use, a good helper for your electric bikes. Specification: Material: Steel Type: Hall sensor Magnet quantity: 5 pieces Color: As picture shown Size: dia. 6.5cm / 2.56in Suitable for: most electric bicycles approximate weight 50g Package list: 1 * Bike Pedal Assist Sensor 1 * Magnetic Sheet Note: Please note that the new type and old type of this product will be sent at random, and make sure you do not mind before ordering.