The Chrome Air Valve Knob with Caterpillar Engraved Logo is a durable and practical product made of aluminum and treated with industrial hard chrome. It is available in octagon or square shape and fits most makes and models. This air valve knob adds a touch of style to your vehicle while providing easy and convenient control over air flow. With its engraved Caterpillar logo, it showcases a high-quality design. Sold individually, this air valve knob is a reliable and functional accessory for any vehicle.