Review on Test, Measure & Inspect Supplies for Midwest Brewing and Winemaking by Jayme Newitt

Thing stinks, its 8 degree deviation isn't very good when you're trying to measure the temperature of the congestion you're so accurate want to get as possible. I've tried adjusting the nut to calibrate it in a glass of ice water and it seems fine and when I use it again it turns off. Stay away from this piece of shit! Get one from your local HBS so you can return it if you run into problems.