connectors

Where to I get connectors for my thump amp they look like circles and squares in one hole plug it's so I can connect me sub to the amp

Hey everyone, First of all I would like to apologize if this doesnt belong here, any mod or admin can move it where it would fit best. I just got new radio but I see that connectors arent the same. This is picture of my old radio and its connector http://prntscr.com/k16f5j...