Portable air velocity sensors are designed to provide direct, continuous measurements of ultra low air velocity. Its feature velocity ranges as low as 0-0.5 m/s; the highest velocity range is 0-5 m/s. Users can also specify custom ranges, to fit the particular needs of their own applications. The specially designed small sensors allow easy access to obtain measurements even in remote and tight locations. It is used in pharmaceutical, biotechnology, medical device, food & beverage, semiconductor and aerospace.