A new addition to the Bontrager 2010 tire line is the XR2, which comes in different variations. The idea of the Bontrager XR2 Tire is to make purchasing a tire easier while tagging each with different name. For example, the XR2 Tire is made for XC racing, this is where the XR comes into play. The 2 signifies the knob rating on each tire, while the lower number equals less knobs. In total, 6 different models are available starting at 2.1 inch 625 gram wire bead, all the way up to 2.3 inch 675 gram team issue folding Tubeless Ready. Retail starts at $29.99 and goes to $59.99.