2 Piece Bolted Design Incorporates High-Tensile 12.9 Grade Steel Bolts For Reinforcement Of The Caliper Bridge Section,This Offers A Noticeable Performance Advantage Over Conventional Gravity Cast Calipers,Currently Available In Stealth Black/Storm Shadow Blue/Luminous Yellow/Racing Red,Exhibiting Higher Overall Strength And A Comparable Caliper Body Stiffness To Forging,EBC Lightweight-Yet-Strong Aluminum 4-Piston Brake Caliper,Machined From Heat-Treated Low-Pressure Castings,Polyester Coating Process To Ensure They Look Great For Much Longer,Rather Than A Powder-Coated Finish; All Apollo Calipers Use An Advanced High-Temperature Teflon,Computer FEA Analysis Shows That This Offers Significant Improvements In Caliper Stiffness Compared To A Monobloc Design