Circumvention devices are products including game copiers and mod chips that bypass Nintendo’s security enabling a consumer to play unauthorised game files (called “ROMs”) that have previously been downloaded from the Internet or copied from the original disc or cartridge.
Are they illegal?
It is illegal to sell circumvention devices (such as game copiers and mod chips). Nintendo has obtained many decisions from criminal and civil courts across the world that confirms this. It is also unlawful to use these devices when playing unauthorised copies of Nintendo games.