Review on High-Quality Replacement Toner Cartridge for Canon 125 CRG-125 - Compatible with ImageClass MF3010, LBP6030w, LBP6000 Laser Printer - Black, 1 Pack by Valuetoner by Aaron Gordon

. The first one was clean but this newly installed one has stains on the left side as you can see in the photo. I'm pretty sure it's the cartridge because I cleaned everything and the old cartridge still prints clean. Of course, you don't realize a cartridge is defective until you use it, and if you buy more than one cartridge (like me), the return period expires. sooo be careful. Don't buy more than one at a time; You can't be sure what you're getting.