Classic Car Brake Calipers-Do You Want More Pistons -
Amazon.com: SHIMANO Deore XT BL-M8100/BR-M8120 Disc Brake and Lever - Front, Hydraulic, Post Mount, 4-Piston, Finned Metal Pads, Black : Sports & Outdoors
2-Piston vs 4-Piston Bicycle Brake Calipers | Miles Racing