Mr Tuffy Tire Liners Description: Nothing ruins the Zen pleasure of a bike ride quite like getting a flat. That's where Mr. Tuffy tire liners come in as the perfect means to ward off irksome punctures. Made of durable, lightweight, and biodegradable polyurethane, Mr. Tuffy tire liners provide a protective barrier between your inner tube and road hazards such as glass, nails, thorns, and other sharp objects. Color-coded by tire size, Mr. Tuffy will have you covered no matter if you're riding a BMX, road, cyclocross, or mountain bike. Features: Liners are made of a durable, lightweight polyurethane Hardened protective outer layer wards off punctures, ultra-soft inner layer cushions the tube Weighs less than liquid sealants or thorn-resistant tubes Easy to install - no gooey mess Bio-degradable once disposed of in a landfill or composting facility after a long and useful life Includes (2) Mr. Tuffy liners so you can flat-protect a pair of wheels Specifications: Tire Compatibility: 27" x 1", 700c x 20-25mm