Two double-gang electrical boxes bolted together. One box contains the actual module, while the empty box is useful for making connections. The module contains a 3-screw terminal block for a wall switch (up, down, common), IR receiver jack, RF r…eceiver jack, and a user-serviceable 6.3A fuse. A spare fuse is included. There is a 6-wire pigtail for Hot, Neutral, Ground, Common, Up and Down.