toner cartridges manufactured by certified manufacturer by CE, ISO 9001, ISO14000 and STMC.  All the brand names and logos are registered trademarks of their respective owners.Compatible with printers:HP LaserJet Enterprise M506dn HP LaserJet Enterprise M506x HP LaserJet Enterprise M506n HP LaserJet Enterprise M506dn HP LaserJet Enterprise MFP-M527z HP LaserJet Enterprise MFP-M527dn HP LaserJet Enterprise MFP-M527f HP LaserJet Enterprise MFP-M527c HP LaserJet Enterprise M501NSimple installation user:Step 1:Gently rock the cartridge back and forth to spread the tonerStep 2:Pull out the entire sealing tape from the toner cartridgeStep 3:Remove the black paperStep 4:Install the toner cartridge into the printerAll the brand names and logos are registered trademarks of their respective owners. These products are NON-OEM