These printers use the UG-3204 cartridge:
Click On a Printer to View it's Cartridges
Panasonic PanaFax UF-745
Panasonic PanaFax UF-755
Panasonic PanaFax UF-755 E
Panasonic PanaFax UF-755 SE
Panasonic PanaFax UF-775
Panasonic PanaFax UF-775 E