Relay output: Plug and play design with relay output. Easy to program and safe to use. This thermostat plug socket can display Celsius or Fahrenheit degrees. Temperature control range: -40~120/-72~176. Power supply: 100~250V AC 50/60Hz. Temperature control function: Temperature control range Temperature control range: -40~120, Temperature control accuracy: 1%. This digital temperature controller plug is easy to program. Set the start temperature and stop temperature and it will work in heating or cooling mode as programmed. (start temperature > stop temperature, cooling; start temperature < stop temperature, heating). This thermostat plug also supports temperature calibration for more accurate results. Timing functions: F01 to F04 modes for cycle timing and countdown: F01 cycle timing mode; F02 countdown on mode, F03 countdown off mode, F04 countdown on and countdown off mode. You can select F01 mode to control the device to work in a cycle, or F02~F04 mode to countdown timer on or off the device. Setting range: 0~99 hours and 59 minutes. Please note that this thermostat plug only works in one mode. Further features: 3m NTC 10K temperature sensor probe. Large LCD display. Temperature calibration. Reset function. Data storage function, all set parameters can be saved after power failure. Wide range of applications: This thermostat plug socket is widely used in greenhouses, reptiles, incubators, aquariums, freezers, refrigerators, heaters, refrigerators, homebrewers, vivariums, fermentation, heat pads and other temperature control systems.It can also be used as a cycle timer and countdown timer.