Gigablock HP 88 CIS ink system for Officejet Pro K550 L7555 K5400 K8600 L7000 L7380 L7400 L7580 L7680 L7780 Inks made in USA Fits HP printers using HP 88 cartridges 12-15 times more ink volume than OEM cartridges Black w/ pigment ink and cyan, magenta and yellow w/ dye base ink 1 year warranty