As you print more you can save more with hp laserjet toner cartridge dual packs you can reduce your companys printing costs without sacrificing the consistent professional results and reliable trouble free printing of original hp black per cartridge 20 000 pages compatibility hp laserjet 42504350 compatible with hp laserjet 4240 laser printer hp laserjet 4240n laser printer hp laserjet 4250 laser printer hp laserjet 4250dtn laser printer hp laserjet 4250dtnsl laser printer hp lase