Keep recovery and recycling units operating at peak efficiency with a convenient maintenance kit. Contains one quick change filter-drier to be used on both R-12 and R-134a stations, and one 16 ounce bottle of our Premium High Vacuum Pump Oil. For early models using 34430 Filter-Drier (12134A, 17700A, 34700, 34300-2K). See your instruction manual if you have questions about which filter-drier to use.