WinmaX WST Performance Slotted Brake Discs Mazda RX8 300mm diameter rear pair. WinmaX brake rotors offer a performace upgrade over OE discs by using high quality castings and improved cooling to be able to handle more spirited driving on the street or track. Disc Specifications: Diameter (mm): 300 Height (mm): 43 Thickness (mm): 18 Minimum Thickness (mm): 16 Centre Hole (mm): 72 Stud Holes: 5 Weight (kg): 5.9