OKI C9600 / C9650 / C9800 compatible chip
In our experience, the machine rejected the refilled cartridge unless the spent chip was replaced with this compatible chip.
Some customers, however, find that their particular model and/or firmware version can be refilled without changing the chip.
For this reason, once you've cut your teeth on a starter kit, toner bottles and chips are offered separately in the C9600/C9800 product range.
You get ....
Compatible chip that allows the refilled cartridge to print