I needed a 9 volt battery eliminator. It was used in a device that needed a side cable exit so i designed this. The terminals come from an old 9 volt battery and just solder on. There is a cavity inside that can hold a DC voltage regulator (like a CUI P7809-2000-S). I used a switch mode regulator, but if you use a linear regulator (i.e. a 7809) make sure your enclosure can handle the heat.