New type piston steel for the brake caliper

The advance of having the piston in steel instead of aluminum is. It will transfer les heat from the brake pads to the o-ring and caliper than the aluminum one. It will also expand les in diameter than aluminum then the brakes get hot. It is also made so it have a vary little surfers to the brake pads also to reduce the heat transfer, and then it is made in steel will this point last a lot longer.