Briggs & Stratton 5052K Air Filter Cartridge with Pre-CleanerBriggs & Stratton Air Filter Cartridge is used on 12. 5 HP through 20 Gross HP vertical crankshaft L head twin cylinder engines. This pleated paper filter provides the first line of defense against the destructive effects of dirt ingestion. Filter comes with a pre cleaner that adds a second layer of protection against airborne dirt particle ingestion. Air filter cartridge with pre cleaner Filter fits on 12. 5 HP through 20 Gross HP vertical crankshaft