This listing is for a brand new 1/2″ NPT compressed air tool in-line oiler/lubricator. This lubricator has a 5.1 oz oil capacity for air tool oil, it has a fill cap on top along with a oil flow adjustment to control how much oil goes into your airline. This is a must-have for any mechanic or person that uses a lot of air tools. Installing this oiler in your air line will extend the life of your air tools.