Diamond Polished Stainless Steel Brake Caliper Piston Set for BMW/Brembo front brake calipers as found on the F2X M135i/M140i/M235i/M240i, F8X M2/M3/M4 and many more.
In all standard blue M brake calipers there are aluminium pistons that will melt and break down due to heat from track use. With these stainless steel pistons you can run your brakes much hotter without problems. Also airgaps to help cool the area between the brake pad and piston.
Note that these is made for track use and have no provision for dust seals.
Price for eight pistons.