The HT200 is a heat stress WGBT meter that can accurately measure wet bulb globe temperature (WGBT), black globe temperature (TG), humidity (%RH), air temperature (TA), wet bulb (WT), and dew point (DEW). The Heat Stress Index assesses how hot it feels when humidity is paired with temperature, air movement, and radiant heat. Holds up to 50 readings. Comes with a 9V battery and a carrying case.