Refill kits these days are cheap, quick, simple, clean, and did I say cheap.
I'm on my 4th refill of a HP black cartridge, and it looks like I wil have to buy a new one. I have simply worn out this one.
My $35 HP printer has paid for its self over and over.... did I say cheap? It is the backbone of my ebay sales.
...cheap Bob
Newer HP cartridges have a computer chip that tracks usage to prevent it from being refilled.