Maxtor 1/4 height 3.5″ drive. I forget the name for these but they were some of the least reliable hard disks ever made. One very odd aspect of this design (possibly contributing to the problems?) is that it only uses one platter and only one side of the disk!
The head stack is comically simple … one thin film write head and one MR read head.
These drives usually lasted a year or so in service then provided a brief period of degraded super slow service during which you could save some data…. Then they’d up and die.
These images were saved to a Samsung micro SD card with about three times the capacity as the drive pictured which has been in service for about five years.