Epson Progression U12 - Manual (Page 33)

Inserting and Removing Diskettes
If you have a 5.25-inch diskette drive, insert a diskette as
follows: hold the diskette with the label facing up and the
read/write slot leading into the drive, as shown below.
latch
Slide the diskette all the way into the slot. Then turn the latch
down to lock it in a vertical position. This keeps the diskette in
place and enables the read/write heads in the drive to access
the diskette.
When you want to remove a diskette, first make sure the disk
drive light is off. Then flip up the latch and carefully pull out
the diskette. Place it in its protective envelope and store it in a
proper location, such as a diskette container.
1-14 Using Your Computer