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: 3.2 • Dia Imperial: 1/8 • Cut Length Metric: 9.5 • Cut Length Imperial: 3/8 • Overall Length Metric: 61.5 • Radius 1 Metric: 1.6 • Radius 1 Imperial: 1/16