Enhance your truck's interior controls with the Chrome Aluminum Air Valve Control Knob with Jewel. This screw-in air valve knob is made from chrome-plated aluminum and features a decorative jewel on top, a stainless steel script plate, and a 2-inch outside diameter with a 2-inch height and 9/16-inch inside diameter. Options include an amber jewel with tractor script or a red jewel with trailer script, making it easy to select a style suited to your application. Designed as a universal aftermarket replacement part, this semi truck air valve control knob is sold individually and installs with a screw-in application. Its chrome finish and aluminum construction make it a practical choice for replacing a worn or outdated air valve knob while adding a customized appearance to your interior.