Description Manuals Videos Articles This is a replacement air pump part for a CAP-4 filter assembly. Customers Also Viewed CAP- 4 Disconnect, 1/2 inch cl type #22438 $82.45 CAP-4 Ambient Air Pump w/ Frame #22530 $3,676.30 Filter cartridge, Outlet, 2 inch OD x 2-5/8 i… #15030 $50.44