Product information "SCHWALBE TUBE ITEM 6 (20")" Schwalbe standard inner tube no. 6 for bicycle tires in size 20" inch (ETRTO 28/40-406). Retains air for longer than average. Thanks to the best material quality and uniform wall thickness. Maximum reliability that has proven itself millions of times over. ETRTO: 28/40-406 Weight: 95 g Wheel Size: 20 Valve: SV Valve length: 40 mm Bead: Butyl Execution Tube: Standard Item: 6