The transmitter is doing its job after a few uses. However, the quality is not there. I practice cycling and running for a long time with "Polar". The 1st belts were indestructible and have given me satisfaction for many years, both from the point of view of their autonomy as their strength. The latter, made in China have an obvious weakness in the elastic ties. The plastic used in this place is very thin resulting in a short-term breaks. I hope I'm wrong (but this is my second in 2 years - the first was bought in a large sports brand).