Plug-and-play design, LCD screen with a wide viewing angle and backlight for easy temperature reading in poor visibility conditions, and from various viewing angles. Press any button to turn on the backlight, and press the DOWN button to turn off the backlight. The backlight can be set to 10 minutes, 1 hour, 4 hours, 8 hours, or always on. Wide temperature control range. Connect the device to the KT3100BL thermostat socket, set the start and stop temperatures, and the KT3100BL automatically switches between heating and cooling modes, controlling the device to operate as programmed. Temperature control range: -40℃~120℃/-40℉~248℉. Timer and countdown function. Countdown. In addition to the temperature control mode, the KT3100BL socket thermostat has four other modes: Cycle timer mode F01, countdown mode F02, countdown ON, F03 countdown mode countdown OFF, F04 countdown mode countdown ON and OFF. Setting range: 0~99 hours 59 minutes. Please note that it is not possible to use both modes