I bought the TX 3 TH for my somewhat dated WS 7390. My original TX 4 slowly fails his service and I have not really found an accurate indication of an appropriate equivalent transmitter ... The TX-3 TH operated yes temperature and humidity, as well as the originals TX 4 and up with 433 MHz transmission frequency. The most important, he works one hundred percent with my weather station! I so do not have to dispose of and can use them further.