Specification Brand: Charm Blue Model: M2 Waterproof grade: IPX7 Size: 80.5*51*17mm Screen size: 2.4 inches Color: black and white Features: White backlight, IML mirror Weight: 59g Surface Technology, Wireless Cadence/Speed Sensor Heart rate belt/power meter connection. Battery: 40 hours 2.4 inch Anti-glare Screen Japanese professional outdoor anti-glare technology ,data in the screen are clearly visible from all angles. Fast Boot Precise Positioning Switzerland GPS chip, faster positioning and accuracy track record Real Time Display Speed, Average speed, Max speed, Time, Riding time, Date , Trip distance, Total distance, Altitude,Temperature, Gradient, Calories; When connect ANT+ Sensor, display: Cadence, Average Cadence, Max Cadence, HRM, Average HRM, Max HRM ANT+ compatible To get richer riding data by connecting the Cadence sensor, speed sensor and heart rate monitor.famous brands, such as Wahoo ,Garmin and our NEWBOLER. Connect phone APP via Bluetooth, check ,upload and share the riding date to Trainning Peak Cycling data can be saved and shared to Trainning Peakand trainning peaks via XOSS app. The XOSS app fit for iOS 9.0 version and above, iphone 4s and above Any Bluetooth 4.0 enabled Android device with Android 4.3 and above Water-resistant IPX67 Waterproof. Enjoy the cycling experience in all weather conditions. Support for use in rainy weather under the condition of the USB cover is locked properly, please remember to dry it in time.