Fitbit Sense 2

Original owner, used less than one year.

Comes with:
+ Fitbit Sense 2
+ OEM Gray bands (in two sizes)
+ Extra set of black Fitbit bands (in two sizes)
+ 2 stretch fabric bands (blue, black, washable)
+ Original charger
+ 1 spare charger.

Fitbit's most advanced tracker / smartwatch. Tracks workouts, sleep. Also has has cEDA (stress measurement), ECG (atrial fibrillation assessment), SpO2 blood oxygen sensors, heartrate, GPS etc.

Water resistant to 50 meters. Has basic smartwatch functions (notifications, answer / decline calls, Google Maps, Google Wallet, alarms, weather, Alexa assistant, etc.).

Excellent (~ 1 week) battery life.

This is a great fitness tracker - compare to Garmin Venu 2, or Fitbit Versa 4 (similar, but Sense 2 has more sensors than the Versa). Better battery life than smartwatches like the Apple Watch. MSRP price new is ~$300.