The Rock Hawk from CST features an aggressive tread pattern with large, well-spaced lugs. This spacing allows the tire to shed mud and other debris on mountain bike trails with varying conditions. SC - Single compound, one compound throughout the tread optimized for longevity and performance Standard 26x2.25 559 Wire Bk/Bsk 65 975 27 SC NoUPC/EAN/GTIN: 6933882514515