Fitbit Charge 2 Heart Rate + Fitness Wristband, Black, Large (US Version)
PurePulse continuous, automatic wrist-based heart rate tracking to better measure calorie burn all day
Maximize your workouts using simplified heart rate zones (Fat Burn, Cardio and Peak). Splash proof. Do not shower with the device or submerge it in water
See call, text & calendar notifications on the OLED display; Automatically track how long and how well you sleep and wake with a silent vibrating alarm
Get a better understanding of your fitness level and see how you can improve over time with a personalized Cardio Fitness Score; Use Connected GPS during run mode to see real-time stats like pace and distance on your wrist
Track all-day activity like steps, distance, calories burned, floors climbed and active minutes;Find moments of calm throughout your day with personalized guided breathing sessions based on your heart rate, Like all heart rate tracking technologies, accuracy is affected by physiology, location of device, and different movements.
Sync stats wirelessly & automatically to computers and 200+ leading iOS, Android and Windows devices.
Operating temperature: 14 degree to 113 degree fahrenheit, Maximum operating altitude: 30,000 feet
The minimum and maximum circumference range between 170 - 206 millimeters