You will get four disposable chips with 812XL refillable ink cartridges. The chip can be used to replace the whole set of 812XL filled ink cartridges, or it can be used to replace one of the ink cartridges separately. Which ink cartridge chip is used up, just replace it directly. We have a chip holder. When replacing the chip, we only need to remove the original chip and replace it with our chip, which is simple and convenient. IMPORTANT TIPS: DO NOT upgrade printer firmware online ( please close the auto upgrade fuction of printer ).So as not to affect the use of the chip. If you need to buy a complete set of 812XL filled ink cartridges, please search ASIN：B0D56PMXTY. If you have any questions, please contact us through Amazon.