SureGrip® 100 Multi-Spade Speaker Connectors - Fits up to 9 AWG Speaker CablesHigh Purity Purple Copper provides a cleaner, clearer sound compared to the brass or phosphor bronze used in common 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