386590A is a National oil bath wheel seal for trailer wheel RW applications. It is sized for a 4.252 shaft diameter and a 6.007 bore diameter, with a 0.580 seal width. This is a genuine National part from Pro Gear and Transmission, and we are glad to help you match it to your wheel end.FeaturesNational wheel seal, part number 386590AListed for trailer wheel RWOil bath sealShaft diameter 4.252Bore diameter 6.007Seal width 0.580Tech SpecsShaft diameter: 4.252Bore diameter: 6.007Width: 0.580Type: Oil bath