Review on 🌡️ CHENBO(TM) Digital Cooling/Heating Thermostat: 3 Pack with Waterproof Sensor Probe -50-110 °c Temperature Controller - Reliable 12V DC Control, 10A Relay Module by Darryl Blumenthal

These things are great and lots of fun! I was also able to cut the wire between the temp sensor and the board so I could solder a longer wire and keep them further apart and it still worked fine. Google for more instructions on how they work as there are many non-obvious features. There's a whole menu accessed by holding the button down, with about 10 settings or so, where you can control all sorts of things like the power-on delay and the temperature difference between turning it on and off. They have many features that I didn't know when I first bought them. What you need for Google is "W1209"