1.59in l x 1.59in w x 0.49in h. ECG, stress sensing and a skin temperature sensor. Get notifications for calls, texts, calendar events and apps like Gmail and Facebook plus send quick replies and voice replies right from your wrist. Compatibility: Apple iOS 12.2 or higher, Android OS 7.0 or higher, Syncing range: Up to 30ft, Music control via Bluetooth Classic on Android and Bluetooth LE on iOS devices. Built-in GPS + GLONASS, Speaker, Microphone, Multi-path optical heart rate sensor, IR sensors for oxygen saturation (SpO2) monitoring Water-resistant to 50 meters. Battery life up to 6+ days. Heart rate tracking technology. Saves 7 days of detailed motion data minute by minute. International Model - No warranty in the US. In Box: Fitbit Versa 3, Classic wristband (both small & large), Charging cable