Sega Super Prologue 21 

version SKC-1000C. This is a karaoke unit with built-in Sega Saturn. 2 versions exist: SKC-1000 and SKC-1000C. This model powers on but can't boot. A great piece of Sega history, very uncommon outside Japan. I will not go into details but due to how the system worked (downloadable music with subscription), most of the units that can be found now do not have a complete working karaoke part (I have 4 at home and only 1 still works).
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