2.7/8” Universal Threaded Hub Cap, fits 6K, 7K, & 8K 8 bolt axles, Dexter 6K and 8K screw in and Dexter 9K axles (before10/1989). Grease and/or Oil application. Aluminum Powder Coated. Level indication window. Magnetic venting plug that removes metallic particles from your grease/oil lubrication. Grease Zerk fitting access for grease axel conversions.