Apple watch 9 runs latest watch OS 11.5 retail box with Apple care warranty. Didn't use it much, just to track heart rate for some runs and sleep tracking (as it has very accurate gps, heart rate and sleep tracking compared to other watches). 100% battery health, everything works great including sleep apnea feature. Includes band, retail box and charge cord. No locks on it and no problems, you are welcome to pair it to your account on the spot if you want. $250 firm
If you need I can also throw in iphone SE with ios 18.5 for $100 extra that can be used to pair the watch and look at the data it collected as well as run other apps requiring recent iOS version.