Lifeline mtb tubelifelines mtb tube provides excellent value for money the inner tubes have been produced from high quality butyl rubber an old wives tale will tell you that if you buy cheap you buy twice not here this inner tube has been rigorously tested to ensure that there is no air leakage thus ensuring excellent reliability and durability featuresmaterial butyl rubber tube nickel plated presta valve0 90mm thick wallsair leakage testedgreat valuepresta valveincludes lock ring