This is the back portion of the lock. Due to powering issues we couldn't contain everything inside the box so we had to place the Arduino in the back. There are small sections of solder-less breadboards that would just power the systems inside or a transistor for powering certain high current electronics like the solenoid. An interesting technique for keeping the front appearance cleaner is drilling holes in the back of the lock container and feeding the wires through those holes to the Arduino.