The back of a SCSI CD-ROM drive. There's a 50 pin connector, but a 34-pin ribbon cable plugged into it. A 34-pin floppy cable.
https://digipres.club/system/media_attachments/files/112/064/124/692/469/761/original/f04a12c3d3b0224f.jpeg
Here's a different angle. you can see from here that this is a SCSI CD-ROM drive, using a 50-pin connector.
You may notice that the cable plugged into it is slightly smaller.
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