The Dwyer THC Temperature / Humidity Switch simultaneously measures and controls temperature and humidity. The unit offers a 3-digit red display for temperature indication and a 3-digit green display indicating humidity. The Series THC is equipped with four independent relays, two for temperature control and two relays for humidity control. The THC Temperature/Humidity Switch accepts up to two temperature probe inputs (sold separately) and a humidity sensor. A humidity sensor with 0 to 1 V, 3 V (THC-P sold separately), or 4 to 20 mA output can be used with the Series THC.