Medium height ramped center knobs paired with aggressive shoulder knobs provide a fast rolling tire that really bites into corners Medium height ramped center knobs paired with aggressive shoulder knobs provide a fast rolling tire that really bites into corners Race formula triple compound Ideal for technical XC courses EXO equipped models feature Maxxis` EXO sidewall protection which help prevent puncture from sidewall abrasions TR - Tubeless Ready - sealant required SPEED - Triple compound composition where the two compounds in the outer layer are specially formulated to reduce rolling resistance and optimize tread wear and traction