These printers use the 20-100 cartridge:

NEC Superscript 1260

NEC Superscript 1260 N

GCC Elite 12-1200

GCC Elite 1212

IBM 4312 Network Printer

IBM DocuPrint P-12

IBM Network Printer 12

IBM Network Printer 4312

IBM NP 12 Network PTR 12

IBM Superscript 1260

IBM Superscript 1260 N

Lexmark 4312

Lexmark Network Printer 12