Review on High-Quality Digital Temperature Humidity Monitor - 9999ppm by Ben Barrington

As I just received it I can't tell you too much about it. Aside from just seeming to work, the instructions seem well written and I'm looking forward to using it. I just need to figure out what normal indoor CO2 levels should be since my house is 933 and we open the windows every day. I'll let you know. I was surprised that all the stores I've been to have a lot less than 700. The highest was 600. The goal was the best and the lowest.