How to Refill :
This is just Tank Style Cartridges that holding toners only.
The easiest way is making a hole (1/2 inches) on the body anywhere does not have any bumps.
After make a hole. cut off the all burrs with knife in order to put a tape it.
You can refill there. (funnels will be exact fit) and after refilling, Just Tape it
Color: B, C, M, Y