Features1 2Two New 20" x 1.75 to 2.125 Schrader Valve Bicycle Tubes. 3Bulk packaged, no retail packaging is included. Standard 0.85mm thick butyl tube. 432mm Schrader (Regular) Valve / Removable Core. 5Fits 20" bike wheels and 20" upright bicycle wheels. 6Important note for inflating any brand of tube: When replacing the inner tube of a bicycle, carefully check the inside of the outer tube for foreign objects, and ensure that the inner tube is completely placed inside the outer tube. After installation, inflate a little to ensure that the inner tube is completely installed in the outer tube. Once filled, do not inflate it tightly, so it is easy to burst the tire.SpecificationLabeled Size: 20 x 1.75/2.125Valve Type: Schrader ValveValve Length: 32mm (standard bicycle tire Schrader valve length)Tube Compound: ButylTube wall thickness: 0.85mmWeight: about 132gNote These tubes come bulk packaged without any retail packaging included.Please check the side of your tire or on your old inner tube for the proper size, valve type and valve length.Package List2 pcs 20"x1.75 /1.95/2.125 Schrader Valve Bike Tire Inner Tubes