303MF 1" by 5" DoubleStuff Sharpening Stone - Medium & Fine Sided and Includes Protective Case - 303MF

This is my first traditional ceramic sharpener and I have to say I'm impressed. I own numerous other sharpening media including DMT diamonds, glass-based ceramics (expensive water stones affixed to a glass base), Arkansas stones, oil stones, as well as Japanese water stones, but none compare to the portability of this stone and its ease of use. Oh, and did I mention it rarely needs cleaning and never needs flattening? I was a little concerned about the width of the stone as I'd always brought the tool to be sharpened to the stone and at 1" wide I figured I'd have to skew whatever required sharpening so that it wouldn't hang over the edge of the stone. Simple fix: Bring the stone to the tool, which ended up simplifying the sharpening process considerably especially for penknives and kitchen knives. The medium grit feels abrasive to the touch and does a nice job of restoring the bevel on a dull blade, while the fine grit is as smooth as a baby's backside and produces a stunning hone. However, if you have a severely damaged tool and need to reset the primary bevel I'd suggest something more abrasive than the medium grit unless you have a lot of patience and a great deal of free time. A nice bonus is the leather pouch, which is not the smooth leather as shown in the photograph but the rougher variety; exactly the type that takes honing/buffing compound and allows you to strop a 'wicked sharp' edge on whatever you're sharpening (keep the stone in the pouch, apply the compound, then strop to your heart's content.) Overall a superior quality tool that's an all-in-one sharpener that even provides a means for stropping if you don't mind one of the surfaces of the pouch getting a little beaten up and soiled with honing compound. Oh, and did I mention it rarely needs cleaning and never needs flattening?

Good points: -Gives you a very nice polished shaving sharp edge -Product fit and finish is very nice (they took the time to radius the stones!) -Very nice quality leather sheath doubles as a strop for final polishing in a pinch -Ceramic is of the hardest materials known to man, only second to Diamonds -5 inch length provides a workable length to sharpen knives on without being overly awkward -Good value for the money -Ceramic is VERY long lasting and will pretty much never wear out Things to be aware of: (Note I didn't title this "bad points") -Although Ceramic is very hard, it is also brittle by design and will shatter if dropped -Ceramic by it's very nature is a fine abrasive and is more geared towards the finishing process. So if you have a chipped or damaged blade, don't bother using ceramic. You will be there all day! Instead use a different sharpening medium for heavier stalk removal. -Ceramic loads with steel faster than other abrasive mediums such as diamonds or synthetic stones, so they will require routine cleaning. Simply use some Comet cleanser and a NYLON scrubbing pad with water... Do not use steel wool or you will simply load the stone with more steel. Bottom line: Keeping the above in mind, I think this is a great sharpener from a great company. Give it a try!

This is an awesome sharpening stone. Light enough to carry in my camping/hiking backpack, along with a mini strop, but so good I use it for quick sharpening our kitchen knifes at home too if I don’t feel like taking out the Ken Onion Work Sharp and only one of two knifes need a touch up. The pouch is made of leather, and can be used as a mini strop if needed (and it works too), although I ended up buying a separate, larger mini strop for easier, more convenient field use, as I tend to strop several times in between sharpenings. I don’t use water with the stone, I use it dry, and it always puts hair shaving edges on my camping, kitchen and EDC blades (I have used it on High carbon steel camping knifes and axes, and blades with 440C, VG-10, Sandvik 154CM and CTS XHP stainless steels, as well as a few Swiss Army Knifes). For harder steels I prefer diamond stones, as they are faster than ceramic and arkansas stone, but this stone could work out in a pinch, it’d just take longer. This is a great stone, and I’d buy it again.

The stone is ~1" wide ~5" long and ~1/4" thick (25 mm x 6 mm x 126 mm). It is white on the fine side and dark brown on the "rough" side. The edges are beveled all around. The two pieces of stones are likely glued together. The soft case is a brown suede leather with the Spyderco logo on one side. The stone fits well in the case. I got it as a 1st step to hone chip carving knifes, I find the suede leather case works as a strop, the last step is new paper polishing. My knifes glides through wood (basswood and mahogany). I also used the stone to sharpen my flat chisels for cleaning up oak cuts. I see two advantages of this stone: 1) it is used dried therefore no mess (ie no oil, no water). Debris do build up on the stone over time, cleaning up involves a quick rinse with something like Ajax, water, and a scrubber. 2) It does not need to be flattened. I have heard that ceramic stones never wear down (ie cup), though logically it must wear down with use, so the wear is probably unnoticeable. The thickness makes the stone feel delicate, I worry about breaking it when it is held in my hand and pressure is applied while sharpening, so I usually lay the stone on a flat surface so the entire underside is supported (use the case to increase grip). I think it should be thicker, or something should be glued between the stones to increase the heft. This is the only reason I give it 4 stars. This stone is easy to use and works well. I may switch over to ceramic stones completely.

sharpens really well

These are the same stones that are used in the Spyderco Sharp Maker sharpening system, which I own. One side is the grey medium grit stone and the other is the white fine grit. These are flat stone that are meant to be held in your hand and used to polish out any nicks on your blade. the size makes it easy to toss this in a pocket or a pack to take care of your cutting edge on the go. this stone is big enough to use as a small bench stone, but it is thin so you will need to place it on the edge of a block to be able to work the knife on the stone, but it is also small enough to use as a file on the edge of a larger blade. this is not for the beginner to knife sharpening because there isn't any angle guides or instructions that come with this. It is just a double sided stone and a leather case, plain and simple. Care instructions are wash the stones in warm water with a mildly abrasive cleaner, and air dry. this only needs to be done when the metal particles have built up on the stone that it isn't removing much of the blade material when being used. they are made from ceramic, so they will chip easily, so keep them in the storage case when they are not in use. Not that it matters, but the leather case that came with my stone was a much darker brown and is more of a suede style leather.

This sharpener from Spyderco is really rather good. I’ve had one for a few years and turned the leather case into a strop with a bit of jewelers rouge. A little bit of dish detergent on the ceramic stone while sharpening helps to clear away the build up. The ceramic is a fairly fine grit even on the medium side. That being said I don’t use this for profiling mostly just touch ups when I’m out camping or even at home for some of the smaller knifes. The first time I bought this the price was around 28 and at that price it’s a good purchase. The last one I got for a friend more recently and it was up to 35 dollars which let’s be honest is kinda a high price for what you’re buying. Over all a good product that does a good job of putting a sharp edge on a knife. Update It’s June 2020 and the glue of my spyderco double stuff has given out, after a year and a half of hard use I’m left with a very thin smooth and medium ceramic. Still good value for money.

This is a very versatile sharpener for even pocket carry. If you want to be able to touch up your blades even when you are mobile, this is just the thing. No water or oil required! From time to time use scouring powder to clean metal from the pores and it's new again. Unlike the old school whet rocks I used to carry there is no dishing of the surface with wear. Well, nothing lasts forever but this comes close. It will break if dropped on concrete or the like. It is not a coarse stone, so don't count on it to reprofile a blade or to sharpen a blade you have allowed to get really dull. Spyderco classes this as medium and fine. Well enough, those are relative terms, but the medium side is probably less aggressive than what you (or I) think of as medium. That said, I carry this for touching up my already sharp knives. There is no need for me to put deep scratch marks that I'll want to polish out afterwards.