Thats a risk you take when buying a clock on E-Bay, I was caught myself purchasing a T3s with a supposedly new battery installed the previous year only to find out after using it the first season the the battery light was flashing on the clock and needed replacing. The good thing that came out of this was that I was forced into using my ETS system which I already had but never bothered to get it set up and the said T3s after lying around for a few seasons was left at the Linell stand at Blackpool this year to have a new battery installed and clock serviced all in time for the 2018 Young Bird season.