100% butyl inner tube 3.5/4.0-18 TR4

Parts Unlimited inner tubes are manufactured to the highest quality as approved by all the Japanese motorcycle manufacturers. These are "real butyl tubes" made from 100% butyl polymer, unlike many other "butyl" tubes which are a blend butyl polymer with natural rubber. In comparison, 100% butyl tubes minimize natural air leakage while maintaining air pressure for a longer period of time. This tube is a good fit for 110/90-18 and 120/80-18 size tires. These tubes are made by one of the worlds largest tire and inner tube manufacturers. This tube has a metal TR-4 stem, which is a straight stem mounted in the center of the tube.