An aggressive XCall mountain tire, the WTB Trail Boss TCS Light FR 27. 5 excels in most dry to damp trail conditions. Large, tightly spaced lugs provide grip on damp and loose or hard and dry trails, while the Dual DNA rubber compound blends fast rolling 60a rubber in the middle of the tire with grippy 50a rubber on the sides for the perfect balance of cornering and speed. The Light FR version has a single layer lightweight casing to cut down on the ounces, while the Tough and High Grip versions use a more durable double layer Enduro casing. Other than that they're the same, with an all mountain 2. 25 or 2. 4in width, and a light, flexible TCS aramid bead that lets you use tubes or go tubeless.