The Technical Pro Z18.1 is a 18" raw subwoofer. The driver is 18" in diameter with a 120oz. magnet. The connection is a bare wire terminal connection. This speaker can be connected to any standard set up using the bare wire connections. This speaker can push out a total peak power of 2500 watts. The Z15.1 raw subwoofer is the go-to speaker component for a DIY audio engineer or sound designer.