Taper Tube Technology offers variable tube thickness to keep weight down and put strength where you need it. Less unsprung weight and better cooling The latest in tube technology Built with a high grade synthetic and natural rubber blend Heavy outer thickness tapers to a thinner, lighter thickness against the rim Tire Inner Diameter Width Stem Type 10 in. 2.75 in. Tr-4 12 in. 3.25 in. Tr-4 14 in. 3 in. Tr-4 17 in. 3 in. Tr-4 17 in. 4.6 in. Tr-4 17 in. 5.1 in. Tr-4 18 in. 4 in. Tr-4 18 in. 4.6 in. Tr-4 18 in. 5.1 in. Tr-4 19 in. 2.5 in. Tr-4 19 in. 110 mm Tr-4 19 in. 120 mm Tr-4 21 in. 3 in. Tr-4