Great deal on a set! This is a working Super Famicom Super Mario Kart game cartridge. It has been inspected and cleaned, and is fully functional. It has not been disassembled for cleaning. As an option, I can replace the internal battery with a new one for an additional 250 yen (per cartridge). Please comment if you would like this. As this is an old item, there may be some dirt and yellowing. Please refrain from purchasing if you are concerned about this. I will pack it carefully for shipping.