Features: High strength center lock structure, which can provide strong braking force even during intenses cycling and avoid the influence of rotors stress. The bike disc brake rotors is make of Aluminum alloys and high carbon steel, with high strength, not easily to deforms, and excellent rusts prevention and wear resistance. The polygonal airflows designs and large hole spacing provide good heat dissipation performances and reduce brake attenuation and warpage, thus ensuring excellent brake performances. Excellent dry and wet performances, good wear resistance, quickly ventilation and good heat dissipation. Used as front disc brake bike and rear disc brake bike, easily to install. Specifications: Component: Aluminum alloys and high carbon steel Color: Black/Red/01/Green/02 Diameter: about 16cm/6.3inch Package Includes: 1Pc Bike Disc Brake rotors 6Pcs Installation screws note: Please allow 1-2cm errors due to manual measurement, make surely that you not mind before order. Due to difference between different monitors, the picture may not reflect the actual color.