This is the most commonly used master cylinder for single line (not tandem) systems. Bore size is .70". Made by OE supplier AP/Lockheed, but may be packaged in AP/Delphi or Unipart box. Plastic fluid tank, direct replacement for the Mini's original metal tank master cylinder. Cap included.
See GMC171-OE for metal tank version. For a matching clutch master cylinder, order GMC1008/G.