High-Purity Purple Copper provides a cleaner clearer sound compared to the brass or phosphor-bronze used in common connectors.Direct-Silver 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 supplied tool to create a cold-weld connection between plug and conductor.