Uxcell a15012000ux0527 Carpenter Woodworking 1/4 Inch x 1 Inch 2 Flutes Core Box Router Bit Product Name : Cove Box Bit; Standard : 1/4" x 1";Radius : 12.7mm / 1/2" Cutting Diameter(Approx.) : 25.4mm / 1";Shank Diameter : 6mm / 1/4" Cutting Thickness : 16mm / 5/8";Total Length : 47mm / 1.9"