Filling these refillable cartridges is extremely simple: remove the plug, inject ink, and replace the plug.
The cartridges are the same size as the original Brother cartridges. They can fit up to 20ml of black ink or 13ml of color ink.
These cartridges are built with auto-reset chips. When a cartridge becomes empty, simply remove the cartridge, refill it, and put it back in to reset the displayed ink level to full.
Note that the cartridges are translucent, so you'll always know exactly how much ink you have left inside.
This product contains the following: