13 Wilwood's Superlite 6R calipers use a single, large piston and a pair of small pistons to clamp down on the pads. According to Wilwood, this design is a lot more common with six-piston calipers than most realize. The design allows a pressure differential between the leading and trailing edge of the caliper, which provides an even wear pattern along the entire length of the brake pad, thus controlling brake pad taper. Wilwood notes that this is necessary because incandescent material and debris from the leading edge of the pad is trapped between the pad and rotor; it tends to float the trailing edge of the pad off the rotor. A larger piston at the trailing edge of the pad provides more pressure to compensate for this debris buildup and keep the pad flat against the rotor.