These printers use the Q6511A cartridge:
HP LaserJet 2400
HP LaserJet 2410
HP LaserJet 2420
HP LaserJet 2420 D
HP LaserJet 2420 DN
HP LaserJet 2420 DTN
HP LaserJet 2420 N
HP LaserJet 2420 TN
HP LaserJet 2430
HP LaserJet 2430 DTN
HP LaserJet 2430 N
HP LaserJet 2430 T
HP LaserJet 2430 TN
Canon imageRUNNER LBP 3460
Canon LBP 3460
TROY-Systems Troy 2420
TROY-Systems Troy 2420 /T
TROY-Systems Troy 2420 D/DTSECUEX
TROY-Systems Troy 2420 D/DTSECURE
TROY-Systems Troy 2430