Never seen that exact drive before, but my guess would be it's mechanically similar to this first-gen Mitsumi drive.

Basically, kinda like how a laptop optical drive works where the entire mechanism slides out instead of just a tray. Can't say for certain this is the case with this particular drive, but the overall chunky appearance of the bezel suggests it.

skitters wrote:

What type of CD drive is installed on this computer? http://i.ebayimg.com/images/g/y7kAAOSw4CFYm-so/s-l1600.jpg It has the "Comp […]
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What type of CD drive is installed on this computer?
http://i.ebayimg.com/images/g/y7kAAOSw4CFYm-so/s-l1600.jpg
It has the "Compact Disc" logo on it, but I don't remember ever seeing a CD drive with a bezel like that.
Is it a proprietary drive or just an unusual or early front design?

That's a JPN CDR-H93! It was once bundled with the CD-ROM kit of the PAS16.
It's connected vis SCSI and has a drive-bay which comes out and includes the laser/motor unit (similar to Mitsumi LU005).

Edit: It's also known as CDR-H93MV. See http://www.ebay.co.uk/itm/201060190699
Edit: typo fixed, found picture.
Edit: Specs: double-speed 300KB/s, min. access time 109ms, max. access time 597ms, medium access time 362ms.

Thank you for the information.
Old tech continues to amaze me with its variety.

Those remind me of the Sony DTL-H2510 drives that are part of the Playstaton 1 devkit.

You're right. 😀 The Toshiba XM-4101B also looks a bit like that.