I was excited to get this heart rate monitor because it had such good ratings. I wanted to be able to make sure I was keeping my pulse in te right zone since I have a fast heart rate. Upon arrival, I set it up and tested it in my home and it seemed okay. Today, I took it to the gym for the first time and it would vary between not working at all and saying y heart rate was actually going down as I was working up a sweat! I followed the directions exactly and wet the contacts. And wwhile I was sweating copiously, it said my heart rate was 50. My resting heartrate is around 75 so this was impossible. Then it jump to about 80, go back down to 60, and then stop. Completely useless for me. Maybe it was defective, I don't know. No battery indicator light came on and since I only owned it for 2 days, I doubt that was the problem anyway. Ths is being returned.