Compatible Printer: For HP DeskJet 1050 For HP DeskJet 2050 For HP DeskJet 2050s For HP DeskJet 1000 For HP DeskJet 3000 package contents: 1 pcs black for hp 61xl (CH563WN) FAQ: Q: How to choose your cartridges? You should according to your original ink cartridge model number to when you buying cartridges. Otherwise, Ink cartridge will not work, because the cartridge's chip is not same for different market although the printer model number may be same. This is very important! Q: after the cartridge is inserted into the printer, why does the printer not recognize the cartridge? May you didn't install the cartridge correctly, the cartridge doesn't fit well. So,: 1) Take the cartridge out and re-install it again. 2) Use a dry cloth or paper tissue to clean the chip and then re-install it.