Beryllium-copper is stronger, more conductive, and better sounding than normal phosphor-bronze connectors. Direct-gold plating is optimized for sound. It looks dull because there is no underlying layer of shiny, distortion-causing nickel. Cold-weld system creates an ideal connection with better sound than solder. Slide the no-magnetic-interference ABS casing over the multi-spade, then slide both onto the conductor. Tighten Allen screws with a supplied tool to create a cold-weld connection between plug and conductor.