M3 Fitness Smart band COMBO Pack of 2: If you're a fitness freak and love keeping a track of the calories burnt, sleep cycle, and heart rate, and then the M3 Smart Band is what you need. This smart band works as a heart rate tracker, fitness watch, and an activity tracker.M3 waterproof Smart fitness Band compatible with Bluetooth or Heart Rate Sensor. It is compatible to devices having Bluetooth version 4.0 and below in smartphones, Tablets and PC's and also support Android and IOS.. Working:To connect the smart band to mobile phone, you need to connect the current mobile successfully via Bluetooth. Click unbind icon and band has been successfully connected with the device.: Note: To charge this fitness band you simply need to connect it with the charger charging will get start automatically .