Amana 49694 Carbide Tipped Plunging Round Over 1/8 Radius x 3/8 Dia x 1/2 x 1/4 Inch ShankAmana Tool 49694 Carbide Tipped Plunging Round Over. This bit creates a flat bottom groove between two quarter round shapes. Short vertical walls extending below the radius lend extra depth to the appearance. Depending upon the cut depth adjustment, the radii can be flush with the work surface or recessed. The profile can be formed on an edge using an edge guide or, on the router table using a fence. Diameter (D) 3 8 D1 1 8 Radius (R) 1 8 Cutting