TRACER Bike Disc Brake Rotors with 6 Bolts 160 MM Material: Made of Stainless steel for durability Quick heat dispersionPackage include: 160mm brake disc + 6 x screwsThe hollow design has excellent heat dissipationCompatible with Shimano Tektro Avid Magura HayesEasy to install, lf there is any defective which you received, please contact us and we will give you a satisfaction solution.