Features and Benefits: Precision machined from aircraft aluminum Air stream nozzle has a natural angle for easy use Meets OSHA requirements of special relief hole in nozzle which limits pressure to 30 PSI when dead ended in an air line of 150 PSI or less No need to keep disconnecting an air tool to hook up a blow gun Small compact lightweight durable and easy to useFits permanently between air hose and coupler. 1/4″ NPT Female x 1/4″ NPT Female.