InkOwl Toner Refill Kit for HP CF400A, CF400X, CF401A, CF401X, CF402A, CF402X, CF403A, CF403X (201A/201X) (4-Pack) Includes 4 bottles of Ink Owl premium formulation toner, 4 spouts for easy pouring, easy-seal tape along with detailed, graphic instructions. To refill this cartridge model, you'll need to pierce holes. To do so, it is highly recommended that you use a laser cartridge holemaking tool designed for this purpose. The use of any other tool, including a drill, is not recommended to avoid damaging sensitive internal components. You can then use the provided easy-seal tape to seal the holes. To get the tool: http://www.amazon.com/dp/B008J4P5JU Our instructions will guide you step-by-step through the entire refill process and include pictures showing you exactly where the holes need to be pierced. With this cartridge, it is not mandatory to replace the chip since the low toner error can be bypassed. Since replacement chips for this printer are expensive, we recommend not replacing them. Our instructions will fully detail how to bypass the low toner error. In this way, you can print until the color starts to fade out, and then refill at that point. Includes 35g of black toner powder and 30g of each color for the full 1500-page yield of black and 1400-page yield of color (at 5% coverage) just like the original HP standard-yield cartridges.