These are ideal for engraving and decorative panel work. Made with Solid Tungsten Carbide inserts, with two flutes. Specifications • Shank Diameter: 1/4 • Dia Metric: 4.8 • Dia Imperial: 3/16 • Cut Length Metric: 12.7 • Cut Length Imperial: 1/2 • Overall Length Metric: 66 • Radius 1 Metric: 2.4 • Radius 1 Imperial: 3/32