From Newsgroup: comp.sys.ibm.ps2.hardware

https://www.ebay.com/itm/196816427439

BIN / MAO

For external CD-ROM. DB-37 connector, my hunch it's for a specific
CD-ROM, no idea...

For Models 50, 60, 80. MS-DOS 3.1, 3.2, 3.3 does NOT support OS/2

Card looks to be all SIMMple logic ICs, no controller visible.
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