Expansion Pak

The Expansion Pak was a RAM expander for the Nintendo 64, released in 1999. The Expansion Pak added 4 MB of RAM to the Nintendo 64. It was originally used for the Japan-Only Nintendo 64DD. Worldwide it was used for select Nintendo 64 games. Donkey Kong 64 and The Legend of Zelda: Majora's Mask required it to play. Some games employed the Expansion Pak for improved graphics; most typically, this came as an increase of resolution to 640x480. Without the Expansion Pak, most of Perfect Dark is inaccessible.

When Donkey Kong 64 was first released, a free Expansion Pak was included with each copy for a limited time; later shipments of the game did not include it.