The purpose of this gasket is to act as a high-pressure seal to prevent air leaks between the crankcase head and the Valve Plate assembly.
The original gaskets without the wire mesh tended to become over compressed and brittle over time and air leaks would develop reducing CFM delivery.
Warning:
Never service an air compressor while the unit is still plugged in to any power source or while the unit is still hot severe burns, injury or electrical shock can occur.