− Decrease quantity for Air Filter; ProHDuty Pro Guard; Air Filter; 9 3/8 in. OD x 5 3/8 in. ID x 11 in. H Quantity + Increase quantity for Air Filter; ProHDuty Pro Guard; Air Filter; 9 3/8 in. OD x 5 3/8 in. ID x 11 in. H Add to cart