Carry-On Trailer 2 in. EZ Lube Dust Cap, 2,990 lb. at Tractor Supply Co.
GREASE/DUST CAP AND PLUG (PAIR) - Scamp Trailers
Amazon.com: 2 Replacement 50mm Metal Dust Cap Wheel Hub Trailer Bearing Grease Cover : Automotive
6201 Trailer Wheel Bearing Set | Dust Cap | Dutton-Lainson Company
Amazon.com: Trailer Bearing Dust Cap Wheel - Trailer Axle Grease Cover 1.98" with Extra 2 Rubber Plugs, Bearing Center Replacement Trailer Cup, Trailer Hub Grease Cap for 2000 to 3500 Ib Axles