Hp 45 Printhead Is Also Suitable For Large format Clothing Drawing CAD Plotter.  The Best method To Make Ciss System Refill Ink To The Hp45 Head Cad Plotter Step 1: The air pressure balance in the HP ink cartridge is adjusted by the small vent at the position "C" as shown in the figure. Before filling, "C" must be sealed with tape to prevent ink leakage. At the same time, the small hole shown in the figure "A" should also be sealed with tape. Step 2: HP 45 ink cartridge with green top cover , at the position "B" in the figure, there is a plastic ball covering the filling hole. Use a sharp tool to push the plastic beads into the cartridge to expose the filling hole. The new style ink cartridge (gray top cover) does not have this filling hole, which requires a small drill to drill a small hole with a diameter of about 3 mm at position "B" for ink filling. important If you Refill Ink To The Hp45 Head For Your Large format Clothing Drawing