The Dwyer 473B-1 100 mm Vane Thermo-Anemometer Test Instrument is a versatile unit that quickly and easily measures air velocity or volumetric air flow, as well as air temperature and humidity in imperial or metric units. A stainless steel 100 mm vane probe is included, which has a comfortable hand grip. The extruded aluminum housing of the 473B1 fully protects electronics, yet is lightweight and comfortable to hold.