Unpacked cartridge into the device (SAMSUNG SCX-4521F) introduced and printed test pages. The quality of the print is good, clean and clear. It could be seen on the paper no streaks or spots. Even after several days and print I get still a very good print. What am I supposed to say ... the cartridge doing its job the way it should be and I expect it, even if it is not a genuine cartridge manufacturer. This cartridge is simply right the price for money, I would buy it again, and also to others.