The only name I can find on the package for this style is "Action" so I'm going to assume that that's what they're called. There's a number on the front, so that could also be the name of the style. I have no idea. But this is what they look like:
It comes with four sheets of decals. Each clear sheet containing the stickers is placed on top of a square of pink paper so it makes this pretty colored stripe effect in the package. 
On the back of the package there are some ideas for combining decals to create new designs. There's also some really obvious directions.
Click this to enlarge. There are four distinct styles on each of the four sheets. Skulls, crosses, flowers, hearts, squiggles. The skulls are really cool because...
...When you look up close, the banner across the heart says "Rock, Kiss, Love" in hologram lettering! You may have to enlarge that picture to see it. The writing is SO SMALL, I'm amazed that they included that tiny detail. I love them for it, even though rock kiss love makes no sense.Some of the decals have little metallic "gems" (they're really just flat shiny areas) on them in addition to the matte coloring, another nice touch.
Here I am wearing one of the floral-squiggle-gem decals over Trind Caring Color CC134 (I'll be reviewing this line soon!). The top picture is after a day and a half of wear, the bottom picture is freshly applied. One thing that I really love about these decals is that the clear backing portion is 1) small and 2) really clear. This allows the design of the decal to be the main focus; you don't see a thick clear-ish outline around the design to distract you.
The decals are very thin and delicate but they also adhere really well, a fantastic combination. They lie completely flat, blend in with your polish perfectly and don't peel or curl up.
Honestly, I can't think of anything I don't like about these. I love the designs, the construction of the decals, the coloring, the packaging, the wear time and removal... They're just really damn good decals.
I guess I can think of one thing I don't like- the confusion about the name! Is the name 54031 or is it Action? Is it neither? What is the name?!
And maybe I suppose they're a little close to Ed Hardy territory, but whatever, they're awesome looking skull nail decals!
I don't remember where I got these... It was either Walgreen's or Meijer, but they sell Kiss decals everywhere so you shouldn't have a hard time locating them.