TA Triumph-Adler LP 4140 - Manual (Page 143)

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ADVANCED OPERATION GUIDE 4-11
USB Flash Memory
Connect the USB memory to the USB memory slot on the right side of the
printer. You can then print PDF data stored in the USB memory.
Consult your dealer for USB flash memory usable with the printer.
1 Insert the USB memory into the USB memory slot.
After installation, refer to Using USB Flash Memory on page 2-68.
NOTE: When disconnecting USB flash memory from the printer, be sure
to perform Remove Device in the USB Memory operation menu to
ensure safe disconnection.