Equip your semi truck to be Ready for the Road Ahead™, with the X-tra Seal 4-3/8" TR573 Heavy Duty Brass Tire Valve Stem, a crucial component that allows for the proper inflation of tires. By acting as the entry point for compressed air, this replacement stem allows operators to add or remove compressed air in the case of leaks or over pressurization. Engineered with a durable cap to prevent damage to the metal stem. FleetPride is your First Click in Heavy Duty®.