I used a heart rate monitor from another company for years but somehow lost it. I bought this one recently based on the positive reviews. It's comfortable; that much I can say in favour of it. However, it often doesn't pick up my heart beat at all, and when it does it will fluctuate between non-existent and 190+ bpm. It's clearly a defective product. It is not just sitting on a table, unused. Total waste of money. I strongly recommend against buying this.