Review on 🌡️ HiLetgo 2pcs W1209 12V DC Digital Temperature Controller Board Micro Digital Thermostat -50-110°C Electronic Temp Control Module Switch with 10A Relay and Waterproof by Knate Scarpelli

So far, so good. I really wish they came with instructions! But I figured out the settings P0-P6. P0 - Toggle between turning the relay on when the temperature is above the set threshold or turning on when it is set below the threshold. (C and H indicate that the relay will open when cold or hot. P1 is the hysteresis setting. If this setting is 2 (C) and you have configured the device to turn on at low temperatures when the temperature reaches 30° C reached or less, the relay will turn on when the device heats up above 30°C, it will only turn on the relay at 32°C (30°C + 2°C = 32°C) This will prevent the Your heating/cooling system will cycle on and off rapidly as the unit hovers around the TV Temperature P2 is the maximum temperature so someone messing with this doesn't set your incubator to 50C and kill your eggs or overheat your computer P3 is the same as P2, for P4 - Temperature Correction to correct for inaccuracies in thermometer readings. Use this to calibrate a device with a known good thermometer. So it's a beep. I turned this on and my device reads HHH and I had to turn it off to use it again.