Shows Relative Humidity & Temperature at a Glance.

This Certified Hygrometer Model No. HTAB-169 is certified to be accurate within 3% plus or minus. The dial indicates the complete range of 0 to 100% relative humidity and each instrument has been tested at three different positions of the dial t temperatures ranging from 32 degs. to 230 degs. F under ISO-9001. Over 400 universities, 16,800 industrial plants and 300 hospitals have our humidity indicators in daily use. The moisture driven expansion and contraction of an internal Durotherm™ fiber bundle moves the dial meter. Needs no batteries or external power supply. 5" Dial, 6" overall, solid brass case.