Textile Adviser: Wet and dry bulb hygrometer (a simple instrument for relative humidity test)
Mason's Hygrometer – Sper Scientific Direct
Baker B6030 Wet/Dry Bulb Hygrometer
Wet & Dry Bulb Thermometer
Wet and Dry Bulb Hygrometer Thermometer for Household Greenhouse Wall-Mounted Temperature Humidity RH Monitor
Labworld Wet and Dry bulb Thermometer Hygrometer Humidity meter instrument Wall mounted wooden base for home,workspace and Godawns,28 cm long : Amazon.in: Home & Kitchen