Nickel Plated In-Line Filter Lubricator with 1/2" female pipe threads on both ends. The nickel plating on this aluminum filter lubricator shields the casting and provides abrasive protection which makes it suitable for underground mine operations. Under the nickel plating, the body is made from cast aluminum and has a 1.4 fluid ounce reservoir. Maximum working pressure is 500 psi., and maximum air flow is 30 CFM at 90 psi. Please note: It is necessary to relieve the air pressure in the reservoir after the lubricator has been disconnected from the air line. Depressurization is necessary to keep the oil in the reservoir from continually flowing when not in use.