UCCW is UltimateCustomWidget. The skins shown are not included with UCCW. In fact, there are no skins included in UCCW at all. You have to either download some or make your own. UCCW is really easy to use but at first it can be confusing.
And to the person who did this theme.. I'm quite sad to see these UCCW skins aren't available for download. D: I really like them. As well as the wallpaper. IMO If you didn't make this wallpaper, you should be giving credit to the artist who did.
Otherwise, the theme is really nice dark and clean. Just how I like them.