BikeMaster Tube - 90 Degree Metal Stem (140/90-15) BikeMaster Tubes are made from high-quality butyl rubber, utilize heavy-duty valves, and are manufactured using a very durable seamless construction. It&#39;s the perfect choice to get your bike rolling smooth again!Seamless construction.Best inner tube value available.Butyl rubber inner tube with heavy-duty valve.Tube Specifications:Tube size: 140/90-15.Valve type: PV78 (tall 90&#176; stem).Tube Speci Valve type: PV78 (tall 90&#176; stem).