@vortrex 10mm indeed, mine was a little "stuck" when it came, it helps if you wiggle the nob clockwise and couterclockwise a little, that did the trick with mine, and it runs all the way up to 10 mm
https://www.dropbox.com/sh/otu3w7n0ljz1wax/AACVrPsqLYxVNpRIPBPxdTrza?dl=0
EDIT: I realized you were asking about the IKEDA base IT-VTA-06 not the B-60, my reply doesn't apply
https://www.dropbox.com/sh/otu3w7n0ljz1wax/AACVrPsqLYxVNpRIPBPxdTrza?dl=0
EDIT: I realized you were asking about the IKEDA base IT-VTA-06 not the B-60, my reply doesn't apply