ACDelco Wheel Cylinder - 18E1242 Part #: 18E1242 Line: ACD ACDelco Wheel Cylinder 1 Year Limited Warranty Material: Cast Iron Hardware Included: No Bleeder Screw Cap Included: Yes Bleeder Screw Included: Yes Inlet Thread Size (in): 7/16 Inch Inlet Thread Size (mm): M11 Wheel Cylinder Bore (in): 11/16 Inch Wheel Cylinder Bore (mm): 17mm Show More Show Less