50 pcs 24K Gold Nakamichi Speaker Banana Plug Audio Jack Connector Type: Audio Adapter/Converter Material : Pure Copper., gold plated, Pure copper made, non-magnetic. Package Included: 25pairs ( 25 black + 25 red) Accommodate cable with wire size up to 4mm, Double screws locking, no soldering., Accepts 8AWG to 20AWG speaker wire Double screws locking