Here is a working MFM hard drive controller, made with chips from market leader Western Digital. This is a no name Taiwanese clone of the Western Digital WD1003-WA2, manufactured late in 1989. It supports 2 internal hard drives. This is a 16-bit ISA card, which also includes a controller for one or two floppy drives. 2:1 interleave is the fastest data transfer rate that it can handle.I just pulled this from a 12 MHz 286 system which I saw boot repeatedly from a loud 40MB ST-251 hard drive.Buyer will receive the exact item pictured here, with a 30-day return privilege. I include one 20-pin cable and one 34-pin cable for up to two hard drives. I do not include any documentation or software, but none will be necessary for someone who built or serviced PCs in the late 1980s/early 1990s.