Optical, forearm worn, heart rate armband designed to provide accurate heart rate and calorie burn in a comfortable form factorEquipped with Bluetooth and ANT+ technology to seamlessly pair with fitness apps, smartphones, and GPS bike computers and watchesWorks seamlessly with over 50 apps - including SYSTM, Zwift, Peloton for cycling and Runkeeper and MapMyRun for runningWater-resistant technology and a rechargeable battery that lasts up to 30 hoursANT+/BLEOptical Heart RateBlackUPC/EAN/GTIN: 853988006454