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. Specification: Condition: 100% Brand New Material: Manganese steel alloy Color: Black Overall Length: Approx. 210mm / 8.27inch Cutting edge: Approx. 20.6mm / 0.81inch Opening: Approx. 65mm / 2.56inch Maximum Diameter/Cutting: Approx. 10mm / 0.39inch Package Weight: Approx. 216g Package Included: 1 x Knob Cutter Note: 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. 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 Ideal for removing small branches, protrusions and knobs by cutting into the wood at a concave angle Creates a spherical cut in a hollow concave shape that will heal with the least visible scaring and thus create a more pleasing aesthetic Ergonomic handles gives you a comfortable hold and allowing continuous use without fatigue