This control box is for operating 4 double solenoid accessories such as turnouts and signals or up to 8 uncoupler tracks. The position of the buttons shows the settings for accessories connected to the sockets for those buttons. The control box comes with 8 sockets on the back and a plug on one end and a socket on the other end. All of the connections are for the new plugs from the 71400 sets. 8 appropriate plugs included. Dimensions 80 x 40 mm / 3-1/8″ x 1-9/16″.