LifeTire boasts a flat-free design that resists penetration by nails, broken glass, thorns, jagged rocks, and other sharp objects. Available in 15- by 6-in. front tires and 20- by 10-in. rear tires. Serve as replacement tires for most riding lawn tractors. Require no air for inflation. Made of reinforced polyure-thane, which lasts up to 10 times long-er than pneumatic tires. Comes with guarantee that user wont have flat tires for lifetime of tractor.