What's included:

Fitbit Charge 5
Infinity band (small & large)
Charging cable

Sensors & Components
Optical heart rate monitor
3-axis accelerometer
Built-in GPS + GLONASS
Red and infrared sensors for oxygen saturation (SpO2) monitoring
Device temperature sensor (skin temperature variation available in the Fitbit app)
Vibration motor
Ambient light sensor
NFC
Multipurpose electrical sensors compatible with ECG app & EDA Scan app
Battery & Power
Battery life of up to 7 days. Use of the always-on display and SpO2 features will require more frequent charging. We recommend charging your tracker every few days to ensure you are always tracking.
Battery type: Lithium-polymer
Charge time (0-100%): Two hours
Radio transceiver: Bluetooth
Memory
Saves 7 days of detailed motion data, minute by minute
Saves daily totals for the last 30 days
Stores heart rate data at 1 second intervals during exercise tracking and at 5 second intervals all other times
Water Resistance
Water resistant to 50 meters. After getting the band wet, we recommend drying the band because, as with any wearable device, it's best for your skin if the band is clean and dry. Learn more.

The Fitbit app is compatible with most popular phones. To set up and use your Fitbit products and services, you must install the Fitbit app on a compatible device running one of the following operating systems:

Apple iOS 15 or higher.
Android OS 9 or higher. See additional tips for Android phones here.
Syncing range: Up to 30ft.

Small: Fits wrist 5.1" - 6.7" in circumference

Large: Fits wrist 6.7" - 8.3" in circumference

Window Size
Viewing area: 1.04" diagonal
Screen height: 0.86"
Screen width 0.58"