Primary arms, red dot - Primary Arms Classic Gen II Removable Microdot Red Dot Sight

It just seems to me like these were rejected red dots from Primaryarms and bought at discounted prices by other companies.. I bought two of these and the brightness knobs are so hard to turn. My wife cannot even turn them, and I can barely turn them myself. I actually have to put the knob in the arch between my thumb and first finger two turned it off.. I doubt they’re going to loosen up either, obviously a manufacturing flaw.