Features: Speed sensor The sensor will feed back your stepping situation to the controller, and then the controller controls the motor to work, so as to achieve the mode of helping you move forward. High performance Designed for electric bicycle, the speed sensor is relatively simple. The small magnetic steel and induction contact in the figure sense each other, so as to transmit the information such as stepping speed to the controller. Magnet loop Adapting 12 magnets loop, effectively turn the physical signal and send it to the controller. Universally compatible It has superiority to match well with all electric bicycles available in the market.No need to worry about adaptation High-quality Made of durable metal and plastic material, anti-rust and wear resistant, owing long using life span. Specifications: Type:pedal assistant sensor Material:plastic+metal Item colour:black Model:KT-D12L Interface type:SM Cable length:90cm/35.37inch Diameter:7.4cm/2.91inch Net weight: 52g/1.83oz Packing list 1*pedal assistant sensor 2*tie 1*cable with clamp 1*metal ring