If there is any woodworking maintenance that I dislike, it would have to be changing jointer knives. If there is something that can prolong my eventual removal and replacement of jointer knives I am game to try it. If you hone the edges when you notice them starting to dull, you can whip them back into shape with this hone. Do not count on it to remove the chunks left in your knives from that nail you hit, but the normal wear and tear on jointer and planer knives can be addressed with this inexpensive and easy to use tool. Don’t forget to unplug your tool before use. Stone has 180 grit on one side and 400 on the other. Made in Taiwan.