Polar F6 Heart Rate Monitor.
This guy was amazing for the 2 years I used it. I was into the idea of exercising properly, and researched the benefits of working out based on your heart rate. I loved the challenge of keeping within a certain range and felt so much better than when I was straining to go faster and without direction. Unfortunately, I haven’t run in a couple of years and during that time, the monitor’s battery died. Polar recommends sending the monitor in for battery replacement because the mechanics inside are delicate and should be attended to by a professional.
Well, I’m not going through that, so if anybody is interested in sending it in for a new battery, it’s all yours.