What ink system does the EcoTank ET-5850 use, and what are the ink bottle model numbers?

The ET-5850 uses an EcoTank refillable ink tank system, not cartridges. It uses the 502 series ink bottles: T502120 (Black), T502220 (Cyan), T502320 (Magenta), and T502420 (Yellow).

Report 012456. Filed.