#4.25

RV Square Bumper for Bike Cargo Carrier Hitch Receiver Adapter Mount on RV Travel Trailer Coachman For 4″ square continuous welded RV bumpers (also fits bumpers 4.5″ tall x 4.25″ deep).

RV Square Bumper for Bike Cargo Carrier Hitch Receiver Adapter Mount on RV Travel Trailer Coachman For 4″ square continuous welded RV bumpers (also fits bumpers 4.5″ tall x 4.25″ deep)