HP integrated cartridges are the ones with printhead built-in with the cartridge, such as HP 60, 61, 62, 63, 64, 65, 66, 67, 68 ... Once the cartridge is depleted, HP allows you to keep printing. However, HP will not show ink level anymore. To take this advantage, we modified an OEM cartridge and make it a spongeless refillable cartridge. Product used: https://bchtechnologies.com/modification-kit-for-making-spongeless-cartridge-with-hp-integrated-cartridges-60-61-62-63-64-65-66-67-68-69-70-74-75-901-as-rfc-hpsq/ Required Tools: Sandpaper (prefer 150 grit) Heavy-Duty Utility Knife Two rubber bands Super Glue Long-nose plier