?SIZE? Suitable for 5/16 (8mm) shank hand drills, holder word drive drills. Length of cutting diameter: 7.93/9.52/12.7 mm. ?MATERIAL? This product uses yg6 hard alloy with sharp edge, high hardness, precise positioning, smooth cutting and impact resistance. ?APPLICATION? These 5/16 shank router bits are suitable for solid wood panels, MDF, chipboard, design profiles, for smooth and careful cuts as well as for the production of stylish furniture. They are also suitable for milling grooves on frames, panels, clocks, pylons and other wall tools to create keyhole hangers or to create grooves for cables. ?FEATURES? The hard alloy blade has high-quality welding to provide stable quality and high output, without worrying about broken and sloping problems during your work. The blade is sharp and durable, adopts arc curve design, advantageous to remove, punching is more efficient. ?INCLUDE LIST? Scope of delivery: 1 x T-slot countersink for 1/2 " hexagonal screws; 1 x T-slot countersink for 3/8' hex screws; 1 x T-slot countersink for 5/16 hex screws.