This Brake Master Cylinder Mounting Kit from CSP Germany allows you to install a late Bus Dual Circuit Master Cylinder to your 1955-1967 Bus. When upgrading your Bus to late style disc brakes this adapter kit and Master Cylinder conversion is mandatory.
Learn more from the following Mid America Motorworks Knowledge Library articles:
Air Cooled VW Master Cylinder Typical Removal and Installation Procedure
Air Cooled VW Master Cylinder Typical Bench Bleeding Procedure