Features: Electric bicycle speed sensor (known as PAS, wheel mounted sensor). 1:1 power assist. Make cycling easier and funnier. The electric bicycle assistant sensor is a high-tech component designed for electric bicycle with ergonomics. The electric bicycle assistant sensor has superiority to match well with all electric bicycles available in the market. The electric bicycle assistant sensor employs the dual-magnetic loop - Hall elastic angle difference to detect the dynamic torque, which is converted to DC signal and sent to the controller. Specifications: Condition: 100% Brand New and High Quality Material: Steel Magnets: 12 Disk Diameter: Approx. 65mm/2.56'' Steel Ring Diameter: Approx. 35mm/1.37'' Cable Length: Approx. 1.1m/43.3'' Weight: Approx. 50g Packing List: 1 x Electric Bicycle Assistant Sensor