The 4-Player Adapter (DMG-07) brought multiplayer to the Game Boy. It has a built-in link cable and three further sockets, so up to four consoles could be connected, though only a few games supported four-player mode.
This is a sealed US bundle pairing the adapter with F1 Race, which was one of the most-played multiplayer games on the Game Boy. The adapter also appears in the collection bundled with Top Ranking Tennis and in the US Racing Set.
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