Thermostat; Type 4-Stage, 2-Wire, Wi-Fi Zoning System, Touch Screen, Programmable; Voltage Rating 5 Volt DC; Current Rating 120 Milliamp; Temperature Rating 10 to 40 Deg C; Size 3.15 Inch Width x 1.099 Inch Depth x 4.331 Inch Height; Includes External Sensor, 10 Foot LeadThe THM-0500 is a 4 stage full programmable P.I.D thermostat designed for Hydronic and forced air HVAC applications. The large, full graphic display with a low profile is easy to read and simple to navigate using the touch screen control. The thermostat features a low power idle mode with a dim screen when not in use. When connected to the internet with the Wi-Fi Zoning system, the HBX Zone mobile app allows you to control the thermostat remotely anytime, anywhere. The THM-0500 is designed to work only with the HBX Wi-Fi Zoning System and utilizes only two wires (power and communication) to the ZON-0550 zone control. This eliminates the need to pull wire which makes it ideal for retrofits as well as new installations.