For Print Head Maintenance,Refilling ,Cleaning Kits! Features:The maintenance device is mainly for the problem of air-entering to the print head,vertical and horizontal blank stripe printing.but it won't be helped for the problem of chip damage and electrical faults of the print head!If your printer head is cloged,empty or loses ink volume over time,it will no longer print correctly.Just try to use This smart tool kit to refill with ink into the printer head ,it may Save and Revitalize your print head! For HP Printer head models:18 38 70 72 88 89 90 91 940 941 91 771 789 792 For HP printer models: Officejet Pro K550/K550dn/k550dtwn; K5400/K5400dn/K5400dtn/K5400tn; K8600/K8600dn; L7400/L7480;L7500/L7550/L7555/L7580/ L7590; L7600/L7650/L7680/L7681; L7700/L7750/L7780; PRO K5300; L7380; Officejet Pro 8000-A809a/A811a/A809a/A809n; Pro 8500 - A909b/A909a/A909n/A909g/A910a; Pro 8500A - A910a/A910g/A910n; Designjet 1050/1050C plus/1055 cm/1055 cm plus; T610/T620/T770/T790/T1100/T1120/T1300/T1200/T2300; Designjet 5500/5500PS/5000;Designjet 5000uv/5500 ps uv/5500uv; Designjet Z2100;Designjet Z3100ps/Z3100/Z3200; Designjet Z6100. Note:Do not mix the color when pouring ink to the funnel to refill ink into the printer head