Cinturato SmarTUBE is the cycling inner tube designed for gravel, adventure and endurance. The tube provides all the benefits of the innovative TPU (Thermoplastic Polyurethane) and thanks to a specific formulation delivers the best performances for those who are looking for superior puncture resistance with low weight and compact size. Polyurethane tube Twice as strong as a regular butyl tube Super lightweight Very compact Wheel Diameter: 650B Tube Width: 40-55C Valve Length: 60 mm Valve: Presta Tube Weight: 45 g Shaft Type: Threaded