Never Mind (0.3" Endmill Holder)

[ctwo]

I can't delete posts in this forum, so that must be a knob for fools to turn. I figured out it is a 5/16.


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I see Lyndex NMTB fixed 0.3" endmill holder. Is this likely to be 0.300" or just a loose guess at 1/4"? Is 0.3" a thing, what are you holding in that?

I need a 1/4" holder for my mill, actually Erickson QC30, but I did try a Lyndex and they fit.