Back in the mid-late 80's, when I worked at Howard Medical (a Coco hardware vendor in Chicago), I bought a Sony 720k 3.5" half height floppy drive. I still have it, works great. Curious thing is, it has a jumper to assign the drive as any one of d0, d1, d2 or d3. Never seen such a drive before or since. Chester Costa Rica TI2/KJ4HLT