Air pressure stability. A Schwalbe tube retains air significantly longer. The quality of the materials and the purity of the rubber compound determine the quality of the tube from the very start. During vulcanization, each Schwalbe tube is placed in a mold and inflated. This is the only way to ensure uniform wall thickness and excellent air retention. Reliability. Consistent quality control ensures the highest possible functional safety: each tube is inflated at the factory and stored under pressure for 32 hours to check for air retention. Group tube system. Due to its high elasticity and quality, a single tube covers a wide range of tire sizes. For example, tube No. 17 works just as well with a tire width of 28 mm as it does with a tire width of 47 mm. Only an extremely high-quality and reliable tube can meet this requirement.