Sharpener Tri Hone 6in. Stone AC21. Stone was made to be the most suitable addition to your collection of knife gear. The Sharpener Tri Hone 6in. Stone is made using the Sharpener Tri Hone system which includes triangular shaped sharpening stones with specially designed triangular shaped neoprene pads attached to the stones. These stones are able to produce a very sharp edge probably better than a specially shaped flat iron. For an excellent way to make sure your knife is is some of the sharpest it can be select the Sharpener Tri Hone 6in. Stone. Package Contents: Sharpener Tri Hone 6in. Stone Sharpener AC21: Tri Hone 6in. Stone