This is a tool for inserting ferrules into shafts. Use it when connecting the head and shaft, or when reshafting. Multiple purchases are possible. Please comment in advance. Diameter of the hole in the insertion tool: 10mm Insertion depth: up to 40mm Body size: approximately 60mm long, 22mm wide Compatible with almost all shafts. Wood shaft tip diameters: .335 (8.5mm) .350 (8.9mm) Iron shaft tip diameters: .355 (9.0mm) .370 (9.4mm) [How to use] ① Mark the depth to insert the ferrule with masking tape, etc. (Photo 2) ② Use the ferrule insertion tool to insert the ferrule to the marked position. ※ Be careful not to over-insert. ※ If the ferrule is tight, warming it in hot water will soften it and make it easier to insert. ※ There may be minor scratches on the material. Please refrain from purchasing if you are looking for perfection.