280mm Black Carbon Steel Ryuga Knob Cutter. A must have tool for removing unwanted knobs and stubs from your larger size 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 largest size knob cutter available from this range, Ideal for working on larger trees. There is also a small and medium size available in the same style.