I guess that is the Wii U compatible Gamecube controller that supposedly is very popular with Smash Bros. I do not have one myself but I have the old original GC controllers and they are great.
You will need an adapter too...

You also have the Nintendo Pro Controller - Wii U. The Wii U Pro Controller can be used for playing a variety of games - from packaged games at retail to downloadable games from the Nintendo eShop. Not compatible with the Wii system or games.








