Get the power of continuous heart rate in Fitbit’s slimmest design yet-all day, during workouts and beyond. Alta HR contains a Bluetooth 4.0 radio transceiver. The operating temperature is minus 10 to 45 degree Celsius
With heart rate, you can better measure calorie burn, and use zones (Fat Burn, Cardio, and Peak) to find the right workout intensity for your goals.
With sleep stages powered by PurePulse heart rate, automatically track your time spent in light, deep and REM sleep and take steps toward a better night’s rest.

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【Military Smart Watch】:Support multiple language selection,Synchronize your mobile phone via Bluetooth, you can answer/reject/ make calls at any time. In addition, smartwatch can receive messages notifications from smartphone such as mail,Twitter Facebook, WhatsApp, Skype, etc.
【Vintage Design 】:Mechanical operation vintage electronic smart men’s tactical watch with metal pointer, which looks more sporty,Special composite materials and fully enclosed slim metal shell designed,makes Military Tactical smart watches for men pass dozens of standard tests including temperature, low pressure altitude, dustproof, salt spray, fluid contamination, etc, can undoubtedly become your reliable companion when you like outdoor activities.