The SRAM CenterLine X Rounded Rotor in Centerlock takes the amazingly quiet, smooth, and exceptional cooling capacity of the Centerline and subs in an aluminum carrier to drop grams, further improve cooling, and stiffen the rotor. These particular rotors feature a rounded edge past the braking surface making them safer in mass start events and comply with the UCI's requirements for rotors used in road racing. The Centerline gets its name from the strategically placed vents on the braking surface that help reduce overheating and reduces noise. Better heat management improves performance and lever feel with repeated braking on long descents. Centerline X Rotors feature the same braking surface as the 1-piece CenterLine, however the addition of the aluminum carrier drops weight and stiffens the rotor to improve performance. Dual materials, with different rates of thermal expansion and contraction, help prevent the rotor from warping under heavy use. SRAM chamfers removes the 90-degree corner off the edge of the rotor making it safer for everyone.