I just noticed 4 months late that my bit set was missing the largest bit, instead it was a random bit, same profile of the convex part between two smaller sizes. I never would have thought of measuring them upon arrival. Random error? Will never know but will have to lower my stars for it as the biggest part is the most valuable. However, the part I used worked exactly as requested. I love the fact that this beat does bullnose after bullnose. If you want the bottom piece of wood to have a rounded edge, just flip it over and make that edge. There are cutters that make two edges at once, they have the shape of an hourglass.