Feature: 1. ANT+ and BT design, compatible with most electronic devices, such as bike computer, smartphones, etc. 2. Two usage modes (speed or cadence) can be switched to meet different needs. Remove the battery and reinstall to switch modes. 3. 320h long endurance, don\u0027t worry about running out of battery. 4. IP67 waterproof and dustproof, effectively waterproof without fear of wind and rain. 5. Easy to install and remove. Specification: This is an external sensor that can measure the speed or cadence of a bicycle. Features: ANT+ and BT design, compatible with most electronic devices, such as bike computer, smartphones, etc. Two usage modes (speed or cadence) can be switched to meet different needs. Remove the battery and reinstall to switch modes. 320h long endurance, don't worry about running out of battery. IP67 waterproof and dustproof, effectively waterproof without fear of wind and rain. Easy to install and remove. Specifications: Color: black Material: PC Battery: 1 * CR2032, 3V, 240mAh Waterproof: IP67 Working temp: 0-50℃ Measuring speed: max. 120km/h Measuring cadence: max. 300rpm Item size: 38 * 30 * 10mm / 1.5 * 1.2 * 0.4in Item weight: 10g / 0.4ounce Package size: 137 * 103 * 20mm / 5.4 * 4.1 * 0.8in Package weight: 40g / 1.4ounce Packing List: 1 * Sensor 2 * Rubber Rings 2 * Rubber Pads Package List: Packing List:1 * Sensor2 * Rubber Rings2 * Rubber Pads