Product review (5 stars): Inexpensive hygrometers like this are usually neither accurate or precise
I have 3 of these, purchased at different times.  All read within 1-2 percentage points of a PYLE PTHM-15 low-end scientific hygrometer.  Cant ask for much more than that.  BTW:  Inexpensive hygrometers like this are usually neither accurate or precise.  +/- 5% of a "real" wet-bulb type hygrometer is all you should hope for.