@hifiman5 . Hi Phil, It's roughly 2.5-3" wide 2" thick and 9-10" in width. The neat thing about it is, you take the panel face off, and the brick rests in the bottom of the panel. It has two leads, you trim to fit. One either goes into an existing breaker, or you can buy a dedicated breaker. Trim to length. Insert into breaker, the next line goes into the common. Switch the breaker on. Put the door back on and you are done. Plugged into.... the panel. <3 LOL <3 <3