It actually plugs into the Apple //c serial's port I believe. I would have to pull it out of storage to confirm this. They didnt make very many as it wasnt compatible w/ the regular card based Mockingboard. Here is what I found on the web at: http://www.apple2.org/faq/FAQ.sndmusic04.html The later Mockingboard "D" had the same capabilities as the "C", but attached to the Apple IIc via the serial port. I have everything I need (box, sound device, and manual), except the disk. Would like to make it complete for my collection. -Chris Ryan