Great value product for less than US vendor (Prime member). -Grinded (normal), but by high quality and combination of the two can produce a very smooth surface.I have used the smallest size with both a router and a drill and am very impressed with the results.As with any product, the results will depend on the operator if you so if you are not familiar with fly knives, familiarize yourself with them before you make your first cut, be careful, with this type of knife you have to cut on a hard surface, not on the material, then again and again etc.