These are no ordinary bicycle tubes! These extra strong inner tubes stop flats for 2 years because there is Slime inside. | Slime Tube Sealant seeks out and instantly seals punctures in your tubes up to 1/8" (3mm) using Fibro-Seal Technology | Designed specifically to stop tube punctures from ruining your ride and keep you going | Schrader Valve tube, that installs like any traditional inner tube and full instructions inside every pack | Environmentally friendly. Non-toxic, non-corrosive and non-hazardous, Non-flammable, Water soluble