Plastic Needle Valves are an adjustable method of flow control. Internally, the pin and body create an adjustable orifice that restricts flow. Useful for instances when the exact flow rate hasn't been determined or to compensate for flow variation in other parts of the system. Very fine threads ensure adjustment accuracy. Thread interference increase the friction and reduce the likelihood of vibrations causing a change in the flow rate. All of the Air Logics products are assembled and tested in America. Plastic needle valves are tested for sealing and performance.