About this item Plug and PlayThe digital temperature controller is easy to program and safe to use. Just plug the temperature controller into the socket, select the heating / cooling system, then it works, no wring, LCD with precise display. Heating & Cooling ModeThis digital temperature controller connects to cooling and heating systems at the same time. By setting start and stop temperature, it will automatically switch heating and cooling modes and control the heating/cooling equipment to work. When the start temperature > stop temperature, it will enter the cooling mode; When the start temperature < stop temperature, it will enter the heating mode. Timing Function the digital temperature controller has F01~F04 modes for cycle timing and countdown function. F01: Cycle Timer mode; F02: Countdown ON mode; F03: Countdown OFF mode; F04: Countdown ON and Countdown OFF mode. Timing range: 0-99 hours 59 minutes. Please note that this thermostat plug only works in one mode. Backlight LCD & Various Functions The Backlit LCD display of the digital temperature controller can easily realize showing the temperature control mode, checking the current and setting temperature value, starting and stoping temperature more easily even in a dark environment. Besides, it also has calibration, reset function, screen lock protection function and data storage function that all parameters set can be saved after power off. Multiple ApplianceThis digital temperature controller allows you to precisely control the room temperature, which is widely used for greenhouse, reptile, incubator, terrarium, freezer, refrigerator, heater, fridge, homebrew, vivarium, fermentation, heat mat, and and many places where need to control temperature. It can also be used as a timer for cycle timing and countdown.