The high pressure Adjustable Flow Control Valve adjusts air flow from any high pressure air source for greater comfort. It offers a large gripping handle that makes it easy to use with a gloved hand. From the lowest flow position, the control valve will deliver the minimum flow required by NIOSH. It requires an air supply pressure range from 20 to 45 psig. The Personal Air Cooler is ideal in hot environments, adjusting the air flow from high pressure air sources as low as 25 degrees colder than ambient air for an improved working environment. The personal cooler requires air pressure range of 55-85 psig. Sold by the each.