Product review (4 stars): Amazingly accurate straight out of the box!
I was quite surprised by this product.  Based on the price, I thought it was going to be sub par. But when I salt cap tested this digital thermometer / hydrometer, I was amazed that it was accurate straight out of the box- no calibration was necessary (it read 75% RH after 8 hrs). It does take a while  to accurately read humidity levels, however. But you can leave it on constantly and check it as needed. Comes with Velcro, so you can stick it where you like.  Or you can remove it, and take it with you. This baby sits in my 100 count humidor. Its always on. With three 69% Boveda 60g packs in my humidor, it reads 69-70% RH at 69 to 70 all the time. Great  product at an unbelievable price. Pull the trigger and get it today!