Rolair Air Compressor Pump Oil - 30W Quart (OILCOMP30W34) is the ideal choice for lubricating the moving parts of your air compressor in locations where temperatures are moderate and stay above 40 degrees Fahrenheit on average. The low-foam tendency of the oil helps prevent leaks through the sight glasses, breathers and dipsticks while reducing the chance of oxidation and helping to ensure proper lubrication of the oil. This also makes it easier for the compressor to maintain the right oil temperature. Due to its non-detergent type, the Rolair oil doesn't absorb or hold as much moisture as detergent-type oils. This helps to inhibit rust and oxidation in your compressor so it lasts longer and is able to run properly. Unopened, the non-detergent compressor oil boasts a shelf life of up to five years. Once you pour it into the air compressor, it remains functional for a maximum of 400 hours.