"Bought this thermometer to set up water temperatures of shower units when we install them. Dead simple to use and (so far) reliable.
Comes with a battery installed and also a spare one. Other people have commented that the display shows 'OFF' all the time it's turned off and that this will shorten the battery life, but these LCD displays use such tiny amounts of power it's negligible.
"Easy to use and calibrate,very handy size and clip on unit helps to keep it with you. My only criticism is that it doesn't actually turn off,it does turn off but the display shows permanently off so may run the battery down quicker than if it actually turned off."