All EBC rotors are made from OE spec grey cast iron, exactly as used on new car production and as many as we have tools for are BRITISH MADE wholly in our own UK foundry. Currently EVERY SINGLE ROTOR sold in Europe and the UK is BRITISH MADE and a majority of the designs specific to the USA are also BRITISH made.The British foundry is constantly expanding its in house tooled range but EBC like every brake manufacturer ....does need occasionally to buy some rotors in from approved sources to complete ranges in overseas markets. None of our competitors will ever tell you where their rotors come from and we at EBC are as disappointed as the rest of the world that cost pressure means there is not ONE foundry left in the USA to supply such parts, other brake brands when asked about origin will just sidestep the question. When we do buy rotors in, they are specified, sampled, tested for element analysis, grain structure, tensile strength, hardness and optimum ductility and tested 100 piece by piece to be perfect for runout on this in house machine. 3GD Series Sport Slotted Rotors; Front; For FMSI Pad No. D1371; Vented; 5 Bolt Holes; 338mm Dia.; 73mm Height; 26mm Thick; 79mm Center Hole Dia.; EBC's GD sport rotors features wide aperture slots for cooling to reduce temperatures preventing brake fade. Dimple drilling avoids stress cracks with Thermic black finish with a sleek look whilst preventing corrosion.