In America, the 3DS' Second Circle Pad will be a GameStop ExclusiveS

The Circle Pad Pro, a $20 add-on that adds a second analog input to the Nintendo 3DS—acting as a right analog stick—as well as two shoulder more shoulder buttons, will be sold in the U.S. exclusively through GameStop stores and the GameStop website, Nintendo revealed today.

It will be compatible with Resident Evil: Revelations and Metal Gear Solid 3D: Snaker Eater, among other games.

The add-on is out in Japan, where we've gotten a closer look.