This is a correct master brake cylinder.
The Original 1992 to 1994 and 1992 to 1995 ZR1 Master Cylinder has a M12 x 1.0 thread thread hole for the pressure switch.
Includes Correct Plastic Reservoir (tap for ABS bleed hose), Fluid Level Sensor, & Cap.
Reuse original Pressure Switch (M12 x 1.0 thread) or purchase new.