Product Details: The SKF Heavy Duty Oil Fill Hub Cap is designed to provide superior sealing and protection for your vehicle. Its outer diameter of 6.8750" ensures a snug fit, while an embedded aluminum ring evenly distributes the load. The molded pressure ridge improves sealing ability, and the patented umbrella style valve seals keep out contaminants. The center-fill vented plug-in design is proven to be reliable, and the side fill plug incorporates an O-ring for extra leak protection and a magnet which traps metallic particles. FleetPride is your First Click in Heavy Duty®.