This is the one single brake disc. If you plan to change discs on the entire axle then you should buy two products.
Dimensions and size
Brake Disc Thickness
23
mm
Centering Diameter
55
mm
Height
44
mm
Minimum thickness
21.5
mm
Outer Diameter
258
mm
The state of the art drilling of Brembo® Xtra™ brake discs provides a brilliant and efficient performance in any braking condition, to emphasize the driving style of true enthusiasts. It has been developed on the basis of experience with car manufacturers and the racing world. Brembo® X-tra™ line brake discs offers maximum reliability, performance, and safety. The size, shape, and position of every hole for each specific brake rotors have been carefully designed, studied and tested by Brembo® technicians.