Trend Professional Jointing Router Cutters 10/40X1/2TC - Butterfly Spline Cutter 104 Deg 28mm Diameter x 46mm Cut x 1/2" Shank Key Features: To rout butterfly keys, splines and inlays in timbers and man-made boards Use in conjunction with 104 deg (14 deg) dovetail cutter ref. L120 which cuts dovetail pocket Use in a router table Cut material in two passes to create a butterfly shape, width of butterfly spline is determined by dovetail cutter used Specification: D: 28 mm (metric diameter) C: 46 mm (metric cut length) A: 104 degree (14 degree angle) OL: 84 mm (overall length) Shank Diameter: 1/2 inch