WIX Air Filter w/Fin. WIX HD Air Filters feature premium filtration media with skip a pleat media stabilization (where applicable) and pleat stabilization beads. WIX HD Air filters are recommended for OEM air filter change intervals. Polyurethane and or high strength corrosion resistant end caps and expanded metal bodies ensure a durable long lasting filter. Air filter Laboratory Tests per ISO 5011: Minimum efficiency of 99.9% contaminant removal. (Based on Wix 46664 Wix 42803 Wix 46761 Wix 46433 ) Allis-Chalmers Case Cat I-R Massey-Ferguson John Deere Kobelco Other (Outer used w/46522 or 46514 or 42679 or 42924) - if outer filter needed w/o the fins use 49420.