For the record, Green Guard is the puncture protection belt that is built into the Schwalbe Marathon tires. It's called Green Guard because it's green in color and also because it is partially made of recycled rubber material. This tire has an MSRP of around $40. The Marathon tires should easily be good for 4-6k miles and will last most people 6-8K. They're not the lightest tire in the world but a great commuter/touring tire with a very effective puncture protection belt.