Harley Benton Parts SC-Style Speedknob Gold

To the point: from three knobs that I bought, one of them fitted too loose, making me dubious of how it will behave in a gig situation.
The second fitted too tight (I had to use force in a way that I thought something would crack.
Finally, the third didn't get to the end of the potenciometer pole.
This means that the inner threads of these knobs are manufactured with huge tolerances. I say huge because that feature is critical functionally for this product.
Sometimes it is just not worth it the savings if the thing doesn't deliver.