When you build a PC, there’s a specific place for each component: the motherboard goes in the back of the case, the CPU and RAM plug into their designated slots, hard drives and other storage devices go in drive bays, and expansion cards plug into their slots on the motherboard. What should you do then, if you’re out of storage but have no more 3.5″ or 5.25″ drive bays left? Back in the 1980s, a company called Plus Development came up with a neat solution: a hard drive integrated onto an expansion card.

This one, made in 1987, had been sitting in my junk box for years. I found it somewhere years ago, tried it, couldn’t get it to work, and forgot about it. Today however, I’ll try to get it to running again and find out if there’s still any data inside. Its total capacity is 20 MB, and it connects to a PC through an 8-bit ISA bus.