These 4mm banana plugs make great e-stim connectors.

Rated for 32A, they are solidly built and even stackable, making tri-phase connections quick and easy. They readily accept 2.5mm to 3.5mm wire which can be secured using the screw at the base. Comes with an insulating sleeve that leaves just the plug showing.

Sold in packs of two, with one red and one black connector.