Purchased in Feb to use with my vivo active hr. Used it everyday and worked well until early Aug were it failed to connect to my garmin watch. Thinking it was the battery I opened up the chest strap to replace it. I found a build up of condensation inside the sensor, I allowed it to air dry in the sun and it connected with a new battery. It worked once with a new battery and has failed to connect since. Not the best build quality considering the seal is a thin rubber ring.