DMT W250EFNB 10-Inch DuoSharp Bench Stone Extra-Fine / Fine No Base

The DMT W250EFNB 10-Inch DuoSharp® Bench Stone offers: A wide monocrystalline diamond sharpening surface for versatility Industry leading precision and accuracy A convenient dual-sided design offering fine and extra-fine grits The ability to sharpen dry or with water

Monocrystalline diamond surfaces sharpen faster and more efficiently. View larger.

The versatile 10-Inch DuoSharp® Bench Stone can keep your blade edges at their sharpest for nearly all your home and project applications. View larger.

Click to view all grit sizes available from DMT.

The extra-large diamond surface allows the DuoSharp Bench Stone the ability to sharpen virtually any knife or edged tool, including filet knives, speed skates, plane irons, chisels, and much more.

Its ease of use is equally impressive. You can ditch the messy oils that are required with other sharpeners, and the innovative diamond surface allows you to easily sharpen dry or with water.

Innovative Diamond Surface
DMT's patented DuoSharp surface provides unparalleled performance thanks to its monocrystalline diamond surface, which sharpens faster and more efficiently than other sharpeners. This allows you to spend less time sharpening edges and more time actually using them. DMT uses only the finest materials for their products, and all of their products are made in the USA.

Compact Design
The 10-Inch DuoSharp Bench Stone measures 10 x 4 x 0.38 inches (LxWxH), and it weighs just 1.5 pounds. Its compact and lightweight size make it easy to take anywhere.

About Diamond Machining Technology (DMT)
Since 1976, Diamond Machining Technology (DMT) has been recognized as the leading innovator in diamond sharpening technology. They've pioneered such ground-breaking innovations as the DuoSharp bench stone, the Diamond Whetstone, and the Diafold Magna-Guide Sharpening System--all of which that have revolutionized the diamond knife and tool sharpening industry. Based out of Marlborough, Massachusetts, DMT continues to develop new and exciting diamond sharpening solutions for both consumer and commercial applications.

DMT is committed to developing and producing the world's finest diamond knife and tool sharpeners. DMT takes pride in the fine workmanship of their products, and they only use the highest quality materials in their manufacturing process. All of their products are guaranteed to be free of defects, and any product that doesn't live up to DMT's high standards will be replaced free of charge by the company.

What's in the Box
DMT 10-Inch DuoSharp Bench Stone with extra-fine grit on one side and fine grit on the other.

Find the DMT Sharpener that Meets Your Needs
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That being said, using this tool will leave you speechless. It is that good. First of all, it is large enough to handle anything from a penknife to a 10" slicer with full coverage in a single stroke. Every whetstone should be this size. It is also thin, and isn't consumed during sharpening. The non slip pad provided with the stone works like a charm. Water is the only lubricant used, and cleanup is a snap.

Don't be fooled by the "fine" and "extra fine" rating of it's surfaces. The fine side will fix a badly worn kitchen edge in a few strokes. My guess is that the knife will also be better than new when you are done. The extra fine side will turn good steel into a razor in just a few more strokes. After years of taking time and care to acheive a perfect edge with natural and man made stones, this was an epiphany. The job was so easy, and the results so fantastic, that I went on a sharpening binge and turned over 15 well used knives into razors in little more than 30 minutes.

I also bought the Global sharpening guides for a couple of bucks. They are not needed for small knives, or for an experienced pro, but they make the fine edge look very uniform on longer blades. They give the "factory" look with the custom edge.

This is an incredible tool. By the way, when you are done, you just rinse it and put it away. I doesn't get any better than this!


planes & chisel sharpening   February 6, 2004
David Giles (Seabrook, TX)
25 out of 25 found this review helpful

I purchased this item to sharpen woodworking planes and chisels. Good quality item. Works just as advertised. The larger size allows me to use a Veritas roller jig to keep the blade angle steady (although the jig is not worth the money for other reasons). Water wash off and easy cleaning. The plastic base is worth the extra money IMHO, but the antistick plastic mat works pretty well.

I also used the "scary sharp" system to put a razor sharp edge on the blades. This is a automotive sandpaper on flat plate glass. The DMT fine whetstone is about a 15 micron equivalent where the "sandpaper" goes down to 0.5 micron. The chisel edge shines like a mirror.

My only disappointment was in flattening the backs of old chisels. A coarser grade of diamond is needed for this higher metal removal technique. I tried coarse grade sandpaper, but it wore out quickly. The finer sandpaper grades do not because they only recieve 5-10 strokes after the diamond stone.

For knives and general sharpening utensils, this diamond plate is great. For woodworking, I would buy the coarse / x-fine combination whetstone. Use the coarse side for the one time flattening and the fine or x-fine side for the intermediate surface grinding. Keep one 9"x12" glass plate of really fine micron sandpaper for the final polish.


Great stone   July 7, 2006
S. Allen (Raleigh, NC USA)
13 out of 13 found this review helpful

I researched quite a bit before buying a stone & a steel and I am glad I did.
Oil Stones? forget em they are messy and not nearly as good as the Japanese water stones they wear down and they are slow.
Have a hardness of around 6.5-7 on the Mohs scale and on good knives that have a Rockwell hardness 56-60 and up to 66 they just dont cut it.

Water stones? these are good do a fine job, need to be soaked in water for a few mins, no mess but a good quality Japanese water stone will cost just as much if not more as this diamond stone and most are single grit, they also wear down rather quickly and become useless until you flatten them back out and what do you flatten them with? A big Diamond stone! or Aluminum oxide sand paper like maybe 120-220 grit glued to a piece of glass, which BTW makes a fairly decent sharpening stone on its own (in finer grits 800-2000) that are better than the oil stones.
These are made of Aluminum Oxide in a resin bond, aluminum oxide has a hardness of 9.2 (Mohs) these work better on good knives. These also need to be dried before storing them or they will deteriorate much quicker.

Ceramic Stones? These are good, dont need to be soaked and wont wear out as fast as regular water stones as they are in a "ceramic bond" instead of resin, these are either aluminum oxide or silicon carbide, the carbide is slightly harder at 9.5
These stones will still wear down just not as fast as the regular resin bond water stones.
Both resin bond and ceramic water stones rarely if ever come larger than 8X3" (I have yet to see one, if they exist they would be even more expensive).
This is the only non-diamond stone I would recommend and even then just for a super fine 5000-8000 grit to hone & polish the blade.

Diamond stones? Well this is the only way to go as far as im concerned, no mess at all and if you use water on it the water fills in the pockets and the blade just glides over the stone and stays constantly lubed and cleaned.
These stones cut faster than any other stone have a hardness of 10 (Mohs) and stay flat these are perfect for good steel knives especially the 60-66 (Rockwell) hardness.
The 2 best features of these stones are they stay flat and they are 10X4" which you just cant beat, it gives you nice long easy strokes.
Properly taken care of by the average home kitchen user just sharpening his/her small quiver of knives and in between using a fine steel this stone should last decades.
Using a fine steel everytime you use your knife you should only need to use your stone just a few times a year.

I would suggest this stone DMT 4"X10" Extra Fine & Fine with the Duobase holder which makes it easier to use, then a fine steel like the "F. Dick 11" Multicut Sharpening Steel" which I got here at Amazon also, using this steel makes a HUGE difference and keeps my knife razor sharp.
If you want the perfect polished razor sharp edge also get a Global Ceramic Whetstone, Fine Grit (5000grit) then finish it off with a "Leather Strop" glued to a wooden paddle with a bit of very fine metal polish like white jewelers rouge or flitz and you will have a truly razor sharp and long lasting edge.


Retreat From The Stoneage   January 4, 2003
27 out of 34 found this review helpful

I discarded all my old sharpening stones, stropes, laminated leather wheels, plate glass, powders, Japanese wet stones, slipsticks, and my husband of twenty years, after discovering the DMT sharpening system.

Simply the best sharpening system ever invented.

I own almost every product they produce. The 4" X 10" "Dousharp Extra Fine and & Fine Diamond Whetstone" is a must have for any professional. I use the fold-up model to extend the life of my utility knife (two strokes on each side) and to attract men.


Great sharpeners!   July 22, 2003
Ann (Johnson City, TN)
11 out of 13 found this review helpful

DMT sharpeners are the best on the market! Although a little pricey, the quality is unmatched in my opinion. Why would I want to keep replacing a lower priced model when I can buy DMT and know that it will last me years and years. I sharpen my kitchen knives and pruners- saves me from havng to go out and buy new ones. My husband sharpens his pocket knives, chisels, and lawn mover blades. DMT is worth the investment!