NEW LINK CABLE    for Game Boy Advance & Gameboy Advance SP - 

The Nintendo Game Link Cable is an accessory , allowing players to connect Game Boys of all types for multiplayer gaming. Depending on the games, a Game Link Cable can be used to link two games of the same title, like Tetris, or two compatible games like Pokémon and co-op Super Mario Land. Games can be linked for head-to-head competition, cooperative play, trading items, unlocking hidden features, etc.