MIROO Ink With Updated Version Chips 2Set+2BK High Yield Replacement for hp 934xl 935 ink Cartridge Compatible with HP OfficeJet 6812 6815 Officejet Pro 6230 6830 6835 Printers Package Includes: 4xBlack,2xCyan, 2xMagenta, 2xYellow. Compatible With HP Officejet Pro 6230 6830 6815 6812 6835 6836 All-in-one Printer. High capacity,page yeild:1,000pages/Black and 825pages/Color. ISO-9001 and CE certificate and 1-year warranty service. Before installing the ink , please make the cartridge upside down, then take off the orange cover, and rip off the yellow tape.Please wear gloves prevent do not to get the ink on your hand .