The Wilwood XRZ4R left/right caliper with 1.50"/1.50" pistons is specified for use with a 1.25" disc. This L/R caliper set identifies matching piston diameters on both sides and compatibility with a 1.25" rotor thickness, intended for brake assemblies that call for symmetrical piston sizing and that specific disc dimension.
Wilwood Caliper Type III Ano XRZ4R L/R1.50in/1.50in Piston 1.25in Disc