Very interesting Famiclone inside a Game Boy shell, similar to the Dotcor Boy or Polystation Advance.
The screen only plays some shitty "block zone" games (which is too bad.) Games are stored on a GB sized cart, but it also works with standard Famicom carts with the slot located on the Player 1 controller.
Like the desgin of the buttons on those two controllers there, one seems to have an "analog stick" while the other is more Playstaion like.
Pics blatantly stolen from Ebay where these things go for about $25.