Extremely 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. This tube could come un-boxed. 20 x 1 1/8". Presta or schrader valve.
Best Price: £4.50 from Merlin Cycles