The MTK series low voltage thermostat combines the reliable Sealed-In-Glass mercury-free switch with the latest design technology and contemporary looks. This kit is compatible with most heating applications including single-stage heat pumps and electric heat. No sub-base required and they will mount directly to the wall or on a standard J-Box. They are equipped with a wide range of heat anticipators which allows greater replacement possibilities. Comes factory set to millivolt and converts easily to 24-volt applications. Temperature ranges from 50° to 90°F. Includes 25’ of thermostat wire and connectors to mount on any millivolt valve.