Teravail Standard Tube - 20 x 2.8 - 3 35mm Schrader Valve. The Teravail Standard Schrader Valve tubes feature our widest variety of tube sizes and valve lengths with a proven record of high quality control and consistent availability.0.9mm wall thicknessRemovable Schrader valve coreTeravail Standard packaging features environmentally friendly soy ink printing on recycled cardboardMaster Cartons of Standard tubes contain a total of fifty tubes: five inner cartons of ten individually boxed tubes