Review on Premium Aztech Compatible Toner Cartridge Replacement for HP 58A CF258A 58X CF258X - Black 2-Pack for HP Pro M404/M428 Series Printers by Jonathan Partridge

First of all, this is our second double order and we are very happy with the results (and the savings!). You need a tiny HP cartridge chip to switch to these cartridges (and you'll use that chip in future refills too!). No special skill is required, but if you're shy, just find a teenager. They know how to work with precision and they have excellent eyesight! Seriously, I'm 68 years old and have already changed chips 3 times - NO PROBLEM! If you are still unsure, just watch the video on the product page. It guides you through the whole process! Enjoy and save a lot of money! - Wilhelm