Sega Saturn X-Terminator Ver. 3 

In box with manual. It is like an Action Replay but more powerful: some codes work with XT only and not AR, you can search your own codes and version 3 has an SS Key function (I need to look further on the manual to know how it really works or if someone knows, send me a message).

A lot of different revisions exist. It is uncommon outside Japan.
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