Pot shaft size for dome knobs?

[trenolds]

I've got a quick question. On my DX2, would I need a 1/4" or 6mm shaft size dome knob? I'm not sure if they're basing this measurement off of the part of the shaft that has the split or the part that is threaded. I measured the split part to have less than 1/4", but I'm sure someone has a direct answer.

Thanks.

[Musician78]

I'm quite sure it is the threaded part.

[trenolds]

So it is 1/4" then?

[Musician78]

Does the threaded part measure 1/4" or 6 mm? That is the one that should fit.