In September 1999, the games were announced for release in Japan on 21 November 1999 and a North American release date was estimated for September 2000. Nintendo announced the release of the Pocket Pikachu Color, a full-color portable digital pet similar to the one released the year before. The unit is compatible with "Gold" and "Silver", allowing the transfer of in-game currency known as "watt points". Pocket Pikachu Color was slated for release in Japan on 21 November 1999, the same day as the release of "Gold" and "Silver". In addition, an officially licensed Pikachu-themed Game Link Cable developed by Kemco was set for release in Japan on 18 November 1999. The product functions like a normal Game Link Cable and consists of a yellow cable with a figure of Pikachu on one end, and a Poké Ball on the other.