My Brother HL-2170 left black spots on the left edge of every printout about every 3 inches. I assumed it was caused by the toner cartridge I bought. I didn't think I had a problem with the drum as cleaning the drum didn't work. I replaced this drum and put the half used toner cartridge back in and perfect prints came out. Understand, the manufacturer was right, sometimes you need to replace the drum. This secondary drum from EZ Ink fitted perfectly and looked well built. Replacing a genuine Brother drum unit costs almost as much as the printer itself. This aftermarket drum was economical enough to try and since it solved the problem, this printer will now be staying in the game.