Originally Posted by
kajero
I've had a Polar F11 for over 5 years. I've always had the battery replaced at Batteries Plus for around seven to eight dollars. The watch was dead and I didn't feel like sending it back to Polar. I figured if i was going to let it stay in drawer, I might was well have Batteries Plus replace the batteries. The guy at Batteries Plus said if he replaced th batteries. I would void the warranty. I really didn't care as I had the watch a long time and figured I'd gotten my use out of it anyway. He replaced the battery and the watch is still running. I think the warranty probably pertains to the waterproofing. Seeing as I don't wear it swimming (like I swim anyway) it didn't matter to me. I also replaced the battery in the chest strap with no problem.