<br><b>The T-502 ink bottle refill replacements are compatible for the Eco Tank printers.</b><br><br><b>Compatible Printer Models:</b><br>Premium ET-7700 EcoTank Printer<br>Premium ET-7750 EcoTank Printer<br>Expression ET-2700 EcoTank Printer<br>Expression ET-2750 EcoTank Printer<br>Expression ET-3700 EcoTank Printer<br>Workforce ET-4750 EcoTank Printer<br>Workforce ET-3750 EcoTank Printer<br>WorkForce ST-2000 EcoTank Printer<br>WorkForce ST-3000 EcoTank Printer<br>WorkForce ST-4000 EcoTank Printer<br><br><b>How we are different from other manufacturers?</b><br>Selected Ingredients: We pick the best raw ink ingredients-powder in the market and test every raw material before putting into production.<br>3 Level of Ink Filtration: 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>Broad Compatibility: We research the printer system and conducted hundreds of experiments to ensure the compatibility to the printing mechanism.<br>Continuous Quality Control: We test every production with the ink density, surface tension, and color accuracy before we ship to our customers. We built out a ink production record bank internally so to preserve every ink production sample.<br><b><br>When do I refill ink?</b><br>1 Generally less than your 10% of the cartridge.<br>2 The printer doesn’t work because of insufficient ink.<br>3 You don't want the current ink.<br><br><b>How to Use Them?</b><br>1.Make sure the printhead is working fine before refill.<br>2.Remove the ink refill bottle cap.<br>3.Peal off the plastic cover of the bottle.<br>4.Insert the ink nozzle into the ink tank<br>5.Screw back the ink refill bottle cap.<br><br>ATTENTION: Mixing different types of ink and without usages for over a long period, it may cause printhead clogging.