What the hell is this connector

[DarkestDiamond]

Call me an idiot, but I just found some speakers in the garage and I have no idea what this connector is called or how to output audio to it. 

https://goo.gl/Mbb4hd

[Glenwing]

You stick unterminated wires horizontally through the holes and screw the cap down to secure them.

[Mazeman03]

i think you fish hook a wire then screw down the red/black thing to hold the wire in place, the red is positive and the black is ground or negative idk. thats what i think at least i had speakers i had to do that with but where i put the wire in look different 

 

but if the top view looks like something plugs into it then im wrong

[Maxxtraxx]

It's a speaker, and it uses speaker wire. Its a simple pair of wires that runs from the speaker to the home theatre setup. To use the speakers with speaker wire you would also need a device that outputs through speaker wire.(figured I'd say it, seems kinda obvious I know)

[thekeemo]

Its for bare wire

there should be a hole once you unscrew it that you route the wire through