Replace your cracked or broken, Air Cooled VW Brake Reservoir Base Grommet, with a brand new base grommet for your VW Brake Fluid Reservoir from Mid America Motorworks.
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