I just wanted to share this thermometer/hydrometer that is sold for incubators but I love it for bins, greenhouse and garage.  I have 3 of them now. They have gone up to 110 F and below 2 F for me and remain accurate. IDK what the temp limits are or how acurate is the hydrometer, but the thermometers are very accurate.  They have high and low memory that has been very useful and  
they are small.-  2 1/2" x 2" x 1/4"

http://www.amazon.com/gp/product/B004XNMG4S/ref=oh_details_o06_s00_i00?ie=UTF8&psc=1

Nice. I might get a couple of those. I just got a couple of very basic ones at petsmart that cost almost as much.

I have one from walmart that is about the same. Cost 7 or 8 dollars as I recall