What this is One pair (red and black) of 4 mm audio binding posts / speaker terminal block connectors for banana plug and barewire speaker connections. Key benefits — why you need it Reliable, lowmaintenance connections for amplifiers, mixers, speakers and microphones. Goldplated zinc alloy construction resists corrosion and improves longterm contact quality. Gold plating enhances signal transmission for stable audio output and consistent performance. Screw terminals provide a secure, vibrationresistant connection without special tools. Main features Compatibility: accepts 4 mm banana plugs and standard speaker connectors; suitable for general audio setups. Materials: goldplated zinc alloy for improved conductivity and corrosion resistance. Dimensions: Dshaped panel cutout 11 × 12 mm; total length 48.6 mm — fits standard panels with the specified cutout. Wiring and fastening: internal wiring screw (5 mm) for quick wire attachment; external tightening screw (6 mm) for firm fixation. Package: contains one pair of singleconnection terminals (red and black). How it solves common problems Prevents poor or intermittent contacts that cause noise or dropouts by providing solid mechanical and electrical connections. Reduces corrosionrelated performance loss thanks to gold plating. Simplifies installation and replacement in existing racks, cabinets or speaker enclosures with standard cutout and screw terminals. Typical applications Retrofitting or building speaker cabinets and amplifiers where reliable bananaplug or barewire connections are required. Studio or livesound patch panels and mixers needing robust, serviceable speaker terminals. Home theater, hi‑fi systems, or PA systems where longterm, corrosionresistant connections improve uptime and audio clarity. Installation notes Requires an 11 × 12 mm Dshaped panel cutout for proper fit. Attach speaker wire under the 5 mm internal wiring screw and secure the connector to the panel using the 6 mm external tightening screw. No specialized tools needed beyond a standard screwdriver. Included in box 1 pair (1 red, 1 black) 4 mm singleconnection binding posts.