These printers use the Q5942X JUMBO cartridge:
HP LaserJet 4250
HP LaserJet 4250 DTN
HP LaserJet 4250 DTNSL
HP LaserJet 4250 N
HP LaserJet 4250 TN
HP LaserJet 4350
HP LaserJet 4350 DTN
HP LaserJet 4350 DTNSL
HP LaserJet 4350 N
HP LaserJet 4350 TN
TROY-Systems Troy 4250
TROY-Systems Troy 4250 /T
TROY-Systems Troy 4250 /T SECURE
TROY-Systems Troy 4250 /TSECURE EX
TROY-Systems Troy 4350
TROY-Systems Troy 4350 N/NT
TROY-Systems Troy 4350 N/NTSECUEX
TROY-Systems Troy 4350 N/NTSECURE