What is this thing sitting in slot 2 of my new DS lite?

What is this thing sitting in slot 2 of my new DS lite? ds lite gba slot Hard wiring a SNES controller to DS Lite via GBA Slot ds lite gameboy slot I believe that the DS have some sort of software recognition in place to prevent DMG Game Boy and GBC games from

ds lite gameboy slot List of Nintendo DS games with GBA connectivity · Contents · Advance Wars: Dual Strike · Bleach: The Blade of Fate · Castlevania: Dawn of Sorrow · Daigasso! Band

dsvr1277 Remove the Game Pak Slot Cover from the Game Pak Slot · With the label side of the Game Boy Advance Game Pak facing away from the Nintendo DS Lite, I question who would win in a fight: the Nintendo DS or the Game Boy Advance? Edited by