HP 970 971 CISS for HP Officejet Pro X model.-1000ml ink tank CISS is included ink inside. You don't need to buy ink.-This item is completed CISS set, therefore you don't need to make CISS for yourself.Advantages:1. Ink tank will not leak.2. 1000ml x 4 capacity.3. ABS material, not easy to break, easier to observe ink level.4. Save 90% cost on prin..