The DuoSharp Plus stones are nicely sized at 8” long by 2 5/8” wide and have two grits on each stone to maximize value. The Plus in the name refers to an area of continuous grit in the otherwise interrupted grit surface of the stone. This area is for sharpening edges with fine points that might be difficult on the interrupted surface. A coarse/fine DuoSharp Plus stone is a good single stone to start a sharpening toolkit.
I do have to question the grit ratings of these stones. I didn't notice anything before using them, but after a day, the 2000 grit actually felt courser than the 1000 grit side of the other stone. Whether that could be a byproduct of other factors or an indication of the more obvious, being that the grit ratings aren't accurate, I don't know. But that seemed to be the main criticism of cheaper whetstones, that their grit ratings often aren't accurate. Or maybe it's less a problem with accuracy and more a difference that most synthetic stones might have in common when being compared to much pricier natural stones?
If your knife is dull, we advise you to start with the diamond stone. After restoring the edge to original shape, de-burr the edge lightly with the ceramic stone in order to get a razor-sharp edge. Use no oil or water. Start by laying the blade flat on the stone, raise the blade spine approx. the thickness of the blade, and start moving the knife in circular motions.
It looks like it can be a Sci-Fi film prop. This is a 2 stage type of sharpening system. You'll get a non slip cushion with it which is at the bottom offering stability for the user. It's ergonomic handle provides a comfortable and easy grip. This cushion offers the stability needed when sharpening and polishing your pocket knife to it's absolute razor sharpness. The sharpener does the work as you hold down the grip and simply place your pocket knife to get sharpened by the motions of the ceramic and diamond sharpener wheels. Simply run your dull knives through the device and you'll get the results you've been looking for. This one will definitely help you when you learn how to sharpen a pocket knife on the Priority Chef.