<b>The 664 ink refill kit is compatible with All-in-One printer models:</b><br><br>Expression ET-2650<br>Expression ET-2550<br> Expression ET-2600<br>Expression ET-2500<br>WorkForce ET-4500<br>WorkForce ET-4550<br>WorkForce ET-16500<br><br><b>Ink capacity:</b><br><br>100ml per bottle.<br><br><b>Page Yield: </b><br>Black 4500 Page. Colors 7500 per ink bottle (At 5% coverage on A4 paper)<br><br><b>Selected Ingredients:</b><br><br> AOPANE picks the best raw ink powder in the market and test every raw material before putting into production. Our remanufactured bottles for Epson are backed by a 100% satisfaction and LIFETIME guarantee<br><br> <b>3 Level of Ink Filtration:</b><br><br> Every ink bottle has to go through 3 level of refinement. We make sure the mixture size is lower than 0.2 um before ship to our customer.<br><br> <b>Strict Quality Control:</b><br><br> We test every production with the ink density, surface tension, and color accuracy before we ship to our customer. We built out a ink production record bank internally so to preserve every ink production sample.<br><br> <b>When do I replacing ink?</b><br><br> Generally less than your 10% of the cartridge.<br><br> <b>How to Use Them?</b><br><br> 1. Open the ink tank part cover and remove the ink tank plug.<br> 2. Remove the plug on the top of the ink bottle, unscrew the ink bottle cover, tear off the bottle seal, and cover the ink bottle cap.<br> 3. Peal off the plastic cover of the bottle.<br> 4. Inject all the ink in the bottle into the ink tank that matches the color of the ink bottle.<br> 5. Screw back the ink refill bottle cap.<br><br> <b>Anything Else?</b><br><br> Different types of ink are generally not allowed to be mixed up.<br><br>