Honeywell Tradeline T87F 1867 The Round Thermostat provides reliable temperature control for 24 Vac heat-only or cool-only systems. This classic gold-colored analog thermostat features a positive off switching mechanism and a 3-terminal wallplate for straightforward installation. Designed with a temperature range of 50 to 90 degrees Fahrenheit (10 to 32 degrees Celsius), it includes a 6-inch cover ring to ensure a clean, professional look on your wall. A staple of home and building control, this unit offers the timeless circular design and simple twist-to-set operation that has made it a trusted choice for decades.