These built-in games are usually designed to complement, rather than replace, the traditional cartridge slot, although some devices omit such a slot entirely, allowing only the built-in games to be played. Typical numbers for the built-in "distinct" games range from as low as three to as high as fifty or one hundred games for more expensive products. The number of "distinct games" is important, because while many NES clones claim to have thousands of built-in games, most of these games are usually nothing more than hacks that allow the player to start the same game at different levels or with different numbers of lives.