Mr. Tuffy:~ Made of durable, lightweight urethane, Mr. Tuffy provides a protective layer between the outer tire and inner tube. Urethane has a property which makes it very elastic. When a thorn or piece of glass attempts to penetrate the Mr. Tuffy liner it comes up against a surface that is both hard and elastic. The object pushes against the surface which gives way while resisting initial penetration.
• Sold in pairs (enough for one bike)
• Shield against punctures from thorns, glass, and road debris
• Gentle toward inner tubes, but also has an even tougher side that's nastier to thorns, glass, and nails