Trouble-free Dual Tire Inflation improves mileage and extends tire life! Constructed of high quality two-ply rubber tubing reinforced with nylon braiding for added strength and durability. Fast Fill Dual Tire Inflation Systems are available in a 4 hose kit for both inner and outer tire inflation ease, or 2 hose kit to service inside tires only. Each kit includes hoses, steel mounting brackets, retainer nuts and stainless steel valve caps. For use with 16" to 19.5" Wheel liners.