Description:This knob cutter has a round concave edge, which is used to cut the bonsai tree burl and root burl, and would make a circular concave incision. In the healing process, tree's sap would cover this incision and let it heal quickly and excellently smooth.Features:Made of high quality manganese steel alloy, high intensity, strong tenacity and wearability.Remove branches by leaving a small indented cut that heals with little or no scar.Creates a spherical cut in a hollow concave shape that will heal with the least visible scaring and thus create a more pleasing aesthetic.Ideal for removing small branches, protrusions and knobs by cutting into the wood at a concave angle.Ergonomic handles gives you a comfortable hold and allowing continuous use without fatigue.Specification:Condition: 100% Brand NewMaterial: Manganese steel alloyColor: BlackOverall Length: Approx. 210mm / 8.27inchCutting edge: Approx. 20.6mm / 0.81inchOpening: Approx. 53mm / 2.09inchMaximum Diameter/Cutting: Approx. 10mm / 0.39inchPackage Weight: Approx. 216gPackage Included:1 x Knob CutterNote:1. Please allow 1-2 cm error due to manual measurement and make sure you do not mind before ordering.2. Please understand that colors may exist chromatic aberration as the different placement of pictures..