These stickers from Panini Group feature art from the Ultimate Spider-Man TV (2012) cartoon.
The stickers are 2⅛" x 3" (smaller than standard trading cards). There are seven stickers per pack.
There are 168 regular stickers, and 24 "Special" stickers coded S1 through S24. Several of the regular stickers feature metallic silver backgrounds, but none of the "S" series stickers feature any special effects. The backs of the stickers are identical except for the different number.
A distribution box contained 50 packs (i.e. 350 stickers per box). But the random distribution wasn't great and even purchasing a box, I didn't get a complete set. You can buy a complete box for $20 on eBay, which pretty much the cheapest Spider-Man sticker box you'll find.
The sticker album was sold separately: