Ambient Weather WS-HT350 Fast Response Air Thermo-Hygrometer with Wet Bulb Psychrometer, Dew Point Meter The fast response thermo-hygrometer - Response Time: %RH: 10 seconds for stabilization in still air, temperature &lt; 0.4 seconds Includes large 1.5 x 1.5" dual digital LCD display with backlight Also calculates dew point and wet bulb (pscyhrometer) Includes carrying case and battery Includes 1 year Ambient Weather Warranty