It is not possible to purchase one without the other. Poké Transporter is companion software that works together with Pokémon Bank to transfer Pokémon from your copies of Pokémon Black Version, Pokémon White Version, Pokémon Black Version 2, and Pokémon White Version 2 to your own private Boxes hosted online through the Pokémon Bank service. After downloading Pokémon Bank, you can download Poké Transporter for no charge.
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