Prepare your semi truck to be Ready for the Road Ahead™, with the Buyers 18" x 18" x 36" Steel Underbody Truck Box that offers increased storage space. To offer an additional space to store tools, equipment, backup materials, and important items, this replacement box features a secure design. Fashioned with a weather-resistant and durable body to endure extreme conditions. FleetPride is your First Click in Heavy Duty®.