The Baldwin RS4634 Air Filter blocks airborne dirt and debris before it can harm your engine. Recessed Closed End ---Heavy-Duty Radial Seal Gasket and End Cap will not degrade under temperature extremes, changes in restriction or vibration ---Flexible Outer Edges makes for easy installation and removal in housings with minimal clearance ---PermaPleat Construction provides even pleat spacing to prevent bunching and prolong element life ---Spiral Glue Binding provides added pleat stability for peak media effectiveness Application Summary: Mack Trucks Cross Reference: Mack 57MD48M, 57MD320M, Donaldson EAF5114.