StopTech Drilled and Slotted Sport Rotors are 1-piece direct replacement brake discs for factory brake systems and stock calipers that look great behind your wheels – and offer significantly improved braking performance. The unique cross-drilling and slotting aids with heat and brake dust dispersal; prevents glazing of the pads; adds bite and improves wet and dry braking performance. Built to last; the black e-coating provides protection from corrosion and the high carbon metallurgy (in most applications) offers quieter operation; better crack resistance and increased performance. Premium e-coated rotor with advanced metallurgy that greatly reduces pad squeal. Especially effective with higher friction, European style brake pad compounds. Drilled & Slotted for increased bite, improved looks and better performance Premium e-coated rotor with advanced metallurgy that greatly reduces pad squeal; Especially effective with higher friction; European style brake pad compounds; Added Molybdenum and Chromium to resist rotor cracking 2006 - 2011 BMW 325i, 2007 - 2013 BMW 328i