The last 40MB drive made, and one of the better ones. The ST-351 was an odd mix of technologies: high areal density (only one disc for 40MB!). but an old-fashioned stepper motor. It indicates that this drive had the unique feature of being jumper-setable for either eight-bit (A) or sixteen-bit (X) IDE operation — in other words, you could use it in an XT as well as an AT or 386.
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