The C9345 Ink Maintenance Box stores ink that gets flushed from the system during print head cleaning. Your printer and its software will let you know when the maintenance box needs to be replaced. Note: C9345 C12C93459 Maintenance Tank Box For Epson WF-7820 wf-7840 wf-7830 wf-7845 L15158 L15168 L15150 L15160 L6558 6578 st-c8000