These are no ordinary bicycle tubes! These extra strong inner tubes stop flats for 2 years because there is Slime inside. No more flats for 2 years! Extra strong because there s Slime inside Instantly seals tread area punctures up to 1/8″ (3mm) in size Seals multiple punctures repeatedly Non-toxic and non-flammable Cleans up with water Tube sizes and valve types available for nearly every type of bike. See the Sizes & Specs tab for size and valve details. Works in bicycles wheelbarrows wheelchairs jogging strollers snow blowers and much more. Stop flats for 2 years! 29 x1.85-2.20