These are for the Samsung series of color laser printers (the CX series). You get the best of an inkjet with individual color cartridges, with the speed and printing quality of a laser printer. The big downside is that if you purchase the Samsung brand toner, it is very expensive. About $50+ per cartridge. This allows you to get all the colors in one pack for about $80. It is still expensive, and yes, kind of a rip-off given how inexpensive it is to actually make toner and the cartridges themselves. But, unless you want to buy a new printer each time ink or toner runs out, this is the most cost-efficient option I have found to get replacement toner for these printers. I had no issue with the printer not recognizing or accepting the toner cartridges (at least the one I have replaced so far), and they do last a long time. This is a subscribe and save item on Amazon so you can have replacements sent at whatever interval works for you.
