These printers use the S2522 cartridge:

NEC NEFAX 635

NEC NEFAX 637

NEC NEFAX 645

NEC NEFAX 647

Sharp FO 550

Sharp FO 4650

Sharp FO 4700

Sharp FO 4970

Sharp FO 5550

Sharp FO 5700

Sharp FO 5800

Sharp FO 6700