Extremely air-tight! Less air loss means having to inflate less. A unique rubber mixture makes it possible. Extremely reliable! Each SCHWALBE tube is individually examined twice at the factory to ensue air-tightness. Special quality control that prevents unpleasant surprises. 40-559---------26 x 1.00 47-559---------26 x 1.10 50-559---------26 x 1 1/4 54-559---------26 x 1.35 57-559---------26 x 1.40 60-559---------26 x 1.50