Brodbeck Radius PlatenOur 36" Radius Platen imitates 72" diameter wheel. It is used to make a shallow hollow grind commonly known as an "S" grind. The "S" grind is used in culinary knives to improve food release and reduce weight. The platen is made of heat treated 4140. The mounting holes are 1 4" 20 and are spaced 5 1 4", 6", and 6 3 4" apart from each other for all of our platens and other brands available on the market. The radius platen is 2" by 8" but it will fit on