210mm Black Carbon Steel Ryuga Knob Cutter. A must have tool for removing unwanted knobs and stubs from your medium and larger sized bonsai trees. This tool gives clean and accurate cuts aiding in a quicker healing time. Use these to gnaw and nibble away knobs and stumps on your bonsai trees. These are the medium size knob cutter available from this range, Ideal for working on medium and larger sized trees. There is also a small and large size available in the same style.