SpeakON Connectors are a type of audio interconnect between amplifier s and loudspeaker s. This connector is specially designed with a locking system to prevent accidental disconnection. SpeakON connectors are an alternative to Amphenol "EP" and TRS connectors. SpeakON connectors are designed to be operated in high power audio. These connector come in two (NL2), four(NL4), and eight (NL8) pole packages, so systems that Biamp or even Triamp are possible without running multiple cables. http://www.neutrik.com/en/lighting/accessories/circular-adapters/na4ljx A trademark of Neutrik. See http://www.neutrik.com/en/speakon/ for more information. Do not confuse with PowerCON connectors.