The "Expansion Pak" is a 4-megabyte Random Access Memory (RAM) cartridge that inserts into the top of the Nintendo 64 game console. There is a removable panel on the top of the console, and the 4 meg Expansion Pak simply slides into the slot. (please follow the instructions included with the Expansion Pak carefully)

The Expansion Pak allows developers to create games with larger worlds, bigger animation sequences, and more complex game play. Total RAM memory will increase to 8MB, allowing players to enjoy select Nintendo 64 games using a "high resolution" option. High resolution mode graphics are more crisp and contain a higher definition than the already brilliant Nintendo 64 graphics.