It's a standard connect for this style. mid way down horizontal holes with finger screw compression securing wires. Works great and allows for easy removal of banana plugs if changing to a application where they cant be used. Can be reused over and over allowing for non permant applications. .
I guess I was hoping for more but at this price it's OK for temporary hook up but I would not trust them for permanent installation on good quality equipment. They are thin plastic, the wire ends are extremely thin brass threads that won't take any stress. The plug end themselves are slender, rotate and fit loose in a standard width amp/speaker output connector. Bending the plug ends out with a small screwdriver to make them thicker helped, but I would not recommend these for anything but bench testing.
These dual banana plugs are decent but nowhere near the qualityof my old Radio Shack plugs. The tolerances are sloppy and the build quality is called into question.I would've preferred to pay more and have a more robust product.