Product Details: The Stemco 4-3/8" Wheel Hub Cap Window Kit is the perfect solution for inspecting your wheel bearings without having to remove the hub caps. This kit is made from high-quality materials to withstand harsh environments and comes with a gasket to help seal the window in place and prevent dirt and debris from getting inside. It meets all the necessary safety and performance standards for your vehicle and is easy to install with all the necessary hardware included for a quick and easy installation. With this kit, you can easily inspect your wheel bearings and keep your vehicle running smoothly. FleetPride is your First Click in Heavy Duty®.