This is a must-have addition to the Parkway Diner. It has two electroluminescent panels and two 3 volt battery packs to power them. I got a step down DC to DC converter and stepped my 12 volts of DC accessory power down to 3 volts to powered both panels. I hid the circuitry in a small hill on which the diner now resides. The real beauty of this add-on kit is the interior detail, the counter and stools, the booths all around the front windows. With such big windows it would be a shame to not have a full interior. The roof has a slightly larger slot for the lighted sign and a more flush underside for the glowing ceiling. The Diner is a great kit to build and having this extra detail prolongs the fun of construction. I'm glad I bought both. You'll get more compliments than usual when people see this lighted diner. It is so much more that a grain-of-wheat bulb shining out of tiny windows. This is high tech and realistic.