Slap a Shimano XTR SM-RT98 Rotor on your mountain bike, and ride with the confidence that comes from knowing your brakes are not going to overheat. A unique, three-layer braking surface consisting of an aluminum core sandwiched between two pieces of stainless steel greatly improves heat dissipation, while a lightweight and stiff aluminum spider keeps the rotor spinning true. As always, Shimano"s CenterLock mounting keeps replacement ultra simple. Product FeaturesMaterial: (spider) aluminum, (braking surface) stainless steel, aluminumAttachment Type: CenterLockCompatibility: Diameter: 140 mm 160 mm, 180 mm 203 mmWeight: (160mm) 114 gManufacturer Warranty: 3 yearsRecommended Use: stopping