the first one I got was dead. They sent me a replacement and it worked fine. very easy to program. If it proves reliable over time I'll add a 5th star. The thermostat is no longer accurate. The reading is 19 degrees higher than the actual temperature. It still turns your devices on and off based on preferences you set, but that's about it. I keep a mechanical thermometer in my pond to keep track of the actual temperature and then adjust Inkbird accordingly. I currently set my thermostat to 97F to keep my pond at 76F. I'm currently looking at other thermostat options.