If it's not apparent, these are 20MB 3.5" MFM drives and probably also bear the Octagon brand. These were really, really awful and mostly purchased by OEMs because they were really, really cheap and would barely last until the warranty on the system was up. Manufacture was in that great technological hotbed, the Philippines. As if that weren't bad enough, their last drives were manufactured in that other hardware hotbed of innovation and quality, Chennai/Madras, India.
After Kalok went belly-up in 1994, Jugi Tandon picked up pieces and set up JTS in--guess where--Chennai. JTS was probably the worst drive that I ever had the misfortune to own--not that Kalok was significantly better.
You really, really, don't want these. I wouldn't be at all surprised if they're factory refurbs.