The reference grade of P/C series with phosphor bronze contacts and silver + rhodium plating
Super thick (1.5 micron) Silver plating directly on polished surface of receptacle and blade. Polishing process again (twice) on the silver plated surface, and then applied final Rhodium plating (0.3 micron). Combination and thicknesses of plating represent the final sound character. Quality of polishing process influences the sound quality.