The first cartridge to require the Expansion Pak add-on for Nintendo 64 was Donkey Kong 64, developer Rare's follow-up to its 16-bit Donkey Kong Country series. The accessory, originally sold by itself in 1998, was bundled with each banana-yellow Donkey Kong 64 cartridge, expanding the market share for the device in the same way that Star Fox 64 helped sales of the Rumble Pak. The Expansion Pak increased the console's base memory from 4MB to 8MB, allowing for higher resolutions, added color depth, and/or other improvements in games designed to support it.