Tozan Shakuhachi Hanko

A new message: "The hanko could be sennin or senshu".

Another message: shakuhachi by the same maker, a very good flute, by the way. Maker's name is "Senshu."
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The flute was made with the highest precision. I'll add pictures of this flute later.

thanks Michael. Senshu the name is. Perhaps shu is the character for autumn (not sure as I can't read the hanko). I can read sen.