Schwalbe SV6 - 20 x 1.10 - 20 x 1.50" Presta - 40mmExtremely airtight! The Butyl rubber compound prevents pressure loss and fewer occassions to inflate. Extremely reliable! Quality control for safer cycling: Each tube is checked twice at the factory to ensure safer cycling. Having the correct pressure means fewer punctures and reduced rolling resistance. 20 x 1. 10" (28 406)20 x 1. 25" (32 406)20 x 1. 35" (35 406)20 x 1. 40" (37 406)20 x 1. 50" (40 406)