Professional Universal --- 4 Pin Speakon Connector. The clamping sleeve is suitable for cables with a diameter of 6-15mm. Waterproof Plug --- C-NL4FC waterproof speaker plug for safer use. User-friendly locking design for easy operation. Good Conductivity --- 30A rms continuous power rating. Copper nickel contacts, good electrical conductivity. Applied --- Used for professional audio, amplifiers, racks, baffles, Speakon cables.