| 摘要 |
PROBLEM TO BE SOLVED: To provide an extension pencil preventing the twisting of a lead of which the length straddles a back chuck and a front chuck and capable of reducing the residual quantity of the lead to the utmost. SOLUTION: The back chuck 15 is arranged in a main body shaft cylinder 12 and the front chuck 16 is provided in front of the back chuck 15. The front chuck 16 is held to a taper part 13 and provided so as to be positioned on the same axial line as the back chuck 15 in the contact state with the leading end of the back chuck 15 when the taper part 13 is screwed in and fixed to the front part of the main body shaft cylinder 12.
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