The HD2717T temperature and humidity sensor/transmitter, indicator, and ON/OFF switch type regulator are integrated for monitoring environmental temperature and relative humidity, as well as calculating parameters such as dew point, optimal humidity, and mixing ratio. It has interchangeable probes, and users do not need to interrupt the work process to replace the probes. There are three types of probes: transverse probe (S.TO)/pipeline installation, vertical probe (S.TV)/wall installation, and split probe (S.TC). S. The probe material of TO and S.TV types is AISI304 stainless steel; S. The TC probe material is AISI304 stainless steel or POCAN (plastic). Its output is 4... 20mA At the same time, users can choose with or without LCD display function according to the requirements of the application site.