Optima Fish Scale or Flat work Shading pen Fixed Handle Tip Medium. What originally started out as a Cheryl Dow design for flat carving was changed slightly via Scott Clinton to become a fish scale pen also. Has advantages over the Pat Kennedy system in that you can make your fish body curved without any troubles. Another advantage is that you need only one tip not 9 or 15 and it costs the same as our other pens. This tip is available in small and large sizes. The medium size is probably the most versatile for most carvers and flat work pyrographers.