The TPI Corporation TASKMASTER 5100 built-in thermostat provides temperature control feature for 5100 series fan-forced 3. 3kW to 20kW electric heater models. The thermostat provides SPST line voltage control for single-phase heaters up to 277V, 25A, or pilot duty control (24-277V) for contactor equipped heaters. This built-in thermostat installs into the heater unit enclosure and operates with a single-pole, single-throw (SPST), low-voltage or line duty switch. Built-in thermostat for heater unit temperature control. Compatible with TPI Corporation 3. 3kW to 20kW 5100 series fan-forced electric heaters. Overall dimensions: 4"H x 6"W x 4"D. Operates with a single-pole, single-throw (SPST), low-voltage or line duty switch. Provides SPST line voltage control for single-phase heaters up to 277V, 25A or pilot duty control (24-277V) for contactor equipped heaters. Thermostat can control temperature from 40 degrees F to 110 degrees F. Meets or exceeds NEC and OSHA standards. 1-year manufacturer limited warranty. ⚠ WARNING: This product can expose you to chemicals including nickel which is known to the State of California to cause cancer, and chromium which is known to the State of California to cause birth defects and/or reproductive harm. For information go to www. P65Warnings. ca. gov. Single pole, single throw (SPST), low-voltage or line duty switch.