Lifeline mtb tube 5 packlifelines mtb tube 5 pack provides excellent value for money the inner tubes have been produced from high quality butyl rubber an old wives tale tells 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 rubber0 90mm thick wallsair leakage testedgreat valuepresta and schrader optionsincludes lock ring and cap