Precision CNC-machined billet aluminum construction. Features differential bore technology, dual seal technology for optimum performance. Hard coated 7075 aerospace alloy pistons and chrome grade 8 hardware. Dual, hidden bleeder for easy bleeding. Quick-change design for easy pad maintenance. Proudly Made in the U.S.A.. For replacement pads, see 1721-2455 or 1720-0215. For use with custom 13″ rotors only.