Stopwatch and Accessories: Wireless Stopwatch Name: Wireless Bicycle Computer Compatible With: Speed/Candence sensor, Heart rate monitor Rechargeable: 800mAh battery Mount: 2 Ways/ handlebar & stem Screen: 2.5inch HD Backlight: 3 modes for day & night Support: Wireless bluetooth 4.0 connect Waterproof: IPX5 Working time: 120 hours without backlight Available for: Any bike wheel size