Panaracer Fire XC Pro Tire - 26x2.1 Black/Red Steel Bead - The Panaracer Fire XC Pro is a true classic. With a mix of varying height center knobs, taller cornering knobs and a colored Silica sidewall stripe, the Fire XC is a great choice for aggressive all-around mountain riding. Great traction and low rolling resistance make this tire the first choice for thousands of seasoned mountain bikers. Go with a proven classic. Go with the Fire XC Pro. - Multi Step Knobs perform well in all conditions without loosing performance or adding rolling resistance - BAX Advanced Extra Cord uses extremely narrow .14mm diameter cord which is woven at a super high density into the casing for lightness and flexibility and improves resistance to cuts and abrasions - Silica Compound; adding silica to tire treads improves tire life, durability and grip.