GBA Wireless Adapters Needed for 2-Game Pokémon Trade: Only One Required

You need one (1) Game Boy Advance Wireless Adapter total.

The adapter plugs into the Game Link Cable port (not Link Cable itself) of one GBA/SP. The second GBA/SP connects via the adapter's short cable. Both players insert their Pokémon carts (FireRed/LeafGreen/Emerald). The adapter enables wireless communication for Union Room / Mystery Gift.

Note: Only works with Gen 3 games (FR/LG/E). Does not work with Ruby/Sapphire/Colosseum/XD (no wireless support). Original Link Cable works for all Gen 3 trades without adapter.