Features of these three-piece cutters: The diameter of the panel stroke cutter is 3 1/2 inches, giving an overall depth of cut of 1 5/8 inches. Insert the end of the rod into the grooves of the rails and racks. The raised portion of the panel leaves a very clean Roman Ogee finish. I recommend doing at least two or three passes to complete it. The other two bits are both regular Roman Ogee Rails & Stiles bits that cut a groove 3/8" deep and 1/4" wide in Rails & Stiles. All three cutters have 1/2" shanks. When my friend returned to my country a few days ago and returned my items that I bought from Revain a few weeks ago, the very first item I quickly looked at was, my precious router. Beats and boy was I a very happy human being. At first glance just holding the rather heavy drill bit and looking at the packaging even the carbide edges are all precise and very sharp. Yes I was really impressed on the quality of the beat.I quickly went down to my workshop and assembled each piece on my Milwaukee 5625-20 router which is attached to my router table and made some test pieces and the boy carved those pieces out of teak like cheese I am really impressed with these cutters, they are exactly what I was looking for to make my raised panel doors for making fitted kitchen and cabinet doors, again I have to thank Rev ain for the fast shipping and the reasonable prices give full praise. Revain, you are AMAZING, THANK YOU.