Apple A9M0110 PC 5.25″ 360K Floppy Drive Macintosh SE II Vintage

Untested, This is a vintage Apple PC 5.25 Drive with a beige finish and a built-in cable. The top surface has a series of grooves and the front features an eject button and an Apple logo. The rear panel integrates a built-in cable with a connector. Minor scratches and scuff marks on the top surface Discoloration around the edges of the unit This is an Apple PC 5.25 Drive, model A9M0110, from 1987. It is a fairly specialized Macintosh peripheral, and it is easy to confuse it with Apple's other 5.25-inch floppy drives.

The underside label in your photos gives us the exact identification:

Product: Apple PC 5.25 Drive
Model: A9M0110
Serial: H718013
Manufacturer: Apple Computer, Inc.
Made in: Japan
FCC ID: BCG5U7A9M0110
What it was for

This was not primarily an Apple II floppy drive. It was designed so a Macintosh SE or Macintosh II could read and write standard IBM PC/MS-DOS 5.25-inch floppy disks.

It handles 360 KB double-sided, double-density 5.25-inch MS-DOS media. Apple sold it as part of its push to make the Macintosh more useful in mixed Mac/IBM PC environments. Contemporary documentation describes it specifically as a file-transfer system for standard 360K DOS media.

That made it useful for moving documents between PCs and Macs using Apple's Apple File Exchange software.

It requires a special controller

The connector on the attached cable is a 37-pin D-sub, but that does not mean it is a generic IBM external floppy interface.

The drive normally required one of Apple's dedicated controller cards:

M5023 Macintosh SE PC Drive Interface Card (Not included)
M5056 Macintosh II PC Drive Card (Not Included)

Apple's contemporary documentation explicitly says the A9M0110 requires a PC drive interface card.

It can also work with certain early AST or Orange Micro PC compatibility cards, but that is a secondary compatibility case.

Most importantly, hobbyist reverse-engineering shows that the pinout is not the same as a generic IBM 37-pin external floppy connector, and connecting it incorrectly can damage hardware.

The mechanism inside

People who have disassembled these have found that Apple used a mechanism very close to a Panasonic/Matsushita JU-455-5, a standard-style 360K PC floppy mechanism adapted to Apple's enclosure and controller arrangement.

So functionally, the system is approximately:

Apple Macintosh
→ Apple PC Drive controller card
→ proprietary 37-pin external connection
→ Apple A9M0110 enclosure
→ 360K PC-compatible 5.25-inch floppy mechanism

What it does NOT do

This distinction is important for the listing.

It is not:

an Apple Disk II
an Apple 5.25 Drive A9M0107
a UniDisk 5.25
an Apple II floppy drive
a generic IBM PC external floppy drive

It was specifically made to deal with PC-format 360K disks on supported Macintosh systems.

In particular, it does not let a Macintosh read ordinary Apple II 5.25-inch disks. The disk encoding and controller architecture are different.

Era and historical context

Apple introduced it in 1987, alongside the Macintosh SE and Macintosh II. Apple's March 1987 institutional price list shows:

A9M0110 Apple PC 5.25 Drive: $399 list
M5056 Macintosh II PC Drive Card: $129 list

The drive was scheduled for availability that July.

That makes this a nice transitional artifact from the period when Apple was actively trying to improve interoperability with the dominant IBM PC ecosystem.

Your particular unit

From the photographs:

Field Value
Brand Apple
Product Apple PC 5.25 Drive
Model A9M0110
Serial Number H718013
Drive Type External 5.25-inch floppy drive
Disk Capacity 360 KB
Media 5.25" DS/DD floppy
Intended Format MS-DOS / IBM PC
Interface Proprietary Apple PC Drive interface
External Connector 37-pin D-sub
Cable Permanently attached
Intended Systems Macintosh SE / Macintosh II with appropriate controller
Year Introduced 1987
Country of Manufacture Japan
Color Apple Platinum
Vintage Yes

The housing appears complete and relatively good for its age. There is normal surface wear, marks, minor discoloration and grime, particularly around the cable and connector.