speakON Connector Male 4 Pole

The ProX XC-NL4M SPEAKON Connector Male NL4 is a 4 pole cable connector, chuck type strain relief that fits the industry-standard for loudspeaker connections offer extremely reliable and robust cable connectors with a reliable locking system. They feature solid contacts with screw-type terminals including stranded wire protection.

This professional speaker and amplifier connector offers the industry standard quick lock system.   The internal contacts are touch-proof and are designed to prevent damage from disconnecting under load and include a fail-safe condition for both the equipment and the user.  ...
https://www.proxdirect.com/products/view/548