Specifications:Shank Diameter: 8mm / 0.31"Cutting Diameter: 17mm / 0.67"Cutting Depth: 15.5mm / 0.61"Overall Length: 47mm / 1.85"Tip Material: Tungsten Steel (Carbide)Shank Material: 45# Carbon SteelFeed Rate (suggested): 8-12m/minSpindle Speed (suggested): 18000-24000rpmPackage Included: 1 x Bottom Cleaning Router BitColor: Blue, Silver ToneDescriptions:1. The carbide (tungsten steel) bottom cleaning bits are with sharp cutting edge, high hardness and long life, resulting in nice finishing on woody pieces after cutting.2. Cuts all composition materials, plywood, hardwoods, and softwoods, chipboard, and MDF etc. Great for cleaning up dadoes and grooves. Cannot be used to cut ferrous metal and non wood materials. The larger the tool diameter, the smaller the spindle speed should be.3.