4-pin Speakon Adapter from Swamp, all 4 pins are wired with 1.5mm2 copper conductors.

This adapter is used to connect speakon cables together to enable longer lengths. Suitable for both 2-core and 4-core speaker cables.

A handy accessory to have on hand for those times when you speaker cables are just no long enough.

Connectors: 4-pin Spk(f) - Spk(f)
Wire Gauge: 1.5mm2, 15AWG