Here is a 2 piece, root end, jiari shakuhachi I made
Jiari refers to the plaster-of-paris like paste that is applied inside the bore of the flute. "Ji" means paste and "ari" refers to something existing or being present (arimass).
Rather than relying on the natural walls of the bamboo, the inside of the flute is (usually) fabricated from a combination of tonoko powder and urushi lacquer. After it dries, it is given a final shape, then coated in lacquer.
It's a long process but it produces a uniform sound for ensemble musicians. I don't make too many as I focus on making shakuhachi for people to grow spiritually - not necessarily musically.
I am one of many who believe that the natural bamboo is more conducive to meditation and spiritual development.