Trimming Router Bits are made by Amana Tool, the leading manufacturers of high quality wood cutting tools. Use Amana Tool 47090 Carbide Tipped Flush Trim 1/4 D x 1/2 CH x 1/4 Inch SHK x 2-1/4 Inch Long Router Bit w/ Lower Ball Bearing for laminate work or for template and pattern work. For template application, the bearing follows the template, while the cutting edges trim the workpiece. SPECIFICATIONS: Diameter (D): 1/4; Cutting Height (B): 1/2; Shank (d): 1/4; Overall Length (L): 2-1/4; Replacement Bearing: 47723; Flutes: 2.