Datel Programmable Universal Adapter for the Super Nintendo
This SNES adapter cartridge is best described as a budget version Pro Action Replay MK2 (2.x BIOS) with a limited set of features. The GUI only allows changing the region setting and entering up to 7 access codes, which are meant for getting past any error warnings the adapter can't handle on its own. However, this adapter was released late enough in the SNES era that it appears such codes were never required nor published. It's possible to enter cheat type codes instead (it uses the same PAR code format), although 7E/7F RAM isn't supported and there's no way to toggle effects on/off.
Unlike the PAR2, a domestic game must always be present in the back cartridge port. To boot into the menu, hold Select when powering on the console.
The hidden credits screen at the end of the video is accessed by holding the R shoulder button when booting.