This is great, and totally worth the money. The only knife sharpener I ever had before was a small whetstone. I had a bunch of kitchen knives that were in sad shape, all duller than an HR presentation. I read about this one on Wirecutter, and decided to give it a try. Good purchase.You plug it in, turn it on, and run your knives through a few times on each side. It only runs for a short amount of time, so you don't have to worry about overdoing it. Best of all, it actually works. Those knives are sharp now. You can remove part of it in order to make the openings larger, so that you can sharpen something thicker, such as scissors.Don't use ceramic blades on this.You can also sharpen serrated blades, though not in the same way as straight blades.The sharpening wheels are replaceable, which is great, meaning this is not disposable junk. You can also open it up to get the metal dust out from inside.If you want useful knives again, just buy this. There are supposedly better sharpeners, but they are way more expensive, and I'm not about to bring my blades to Chopped or anything, so I am good. You will be too.