Michelin Airstop tubes are made with 100% butyl rubber, preferred for

 its ability to maintain air pressure over long periods of time 

Butyl is also highly resistant to wear and friction, and easily repaired 

Unlike inexpensive tubes, which are made from straight sections of rubber tube formed into a circle, 

Michelin Airstop tubes are manufactured and cured in a circular mold 

This method reduces tension on the tube when inflated, 

and diminishes the likelihood of pinch flats 

Michelin Airstop tubes are available in a wide array of sizes 

Each size is designed for only a few specific applications, so that tube 

and tire match perfectly without placing undue stress on the tube 

Reinforced tubes available for off-road applications, 

for enhanced protection against punctures