These printers use the UG-5540 cartridge:
Click On a Printer to View it's Cartridges
Panasonic PanaFax UF-7000
Panasonic PanaFax UF-8000
Panasonic PanaFax UF-9000
Panasonic UF 7000
Panasonic UF 8000
Panasonic UF 9000