Reddit reviews Fitbit Charge 2 Heart Rate + Fitness Wristband, Black, Large (US Version), 1 Count

PurePulse continuous, automatic wrist based heart rate tracking to better measure calorie burn all dayMaximize your workouts using simplified heart rate zones (Fat Burn, Cardio and Peak). Splash proof. Do not shower with the device or submerge it in waterSee call, text & calendar notifications on the OLED display; Automatically track how long and how well you sleep and wake with a silent vibrating alarm. Reminders to moveGet 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 wristTrack 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 movementsSync stats wirelessly & automatically to computers and 200+ leading iOS, Android and Windows devicesOperating temperature: 14 degree to 113 degree fahrenheit, Maximum operating altitude: 30,000 feetThe minimum and maximum circumference range between 170 206 millimeters