I like these. The style is clean and unfussy. Screw fixing means they can go on most types of 6mm - 1/4" ish control shafts. Skirt does a fair job of hiding the control fixing nut&washer.
Only a tiny white dot to indicate position, but it works well and is protected from dirt and wear in the recess across the centre line.
Compared to some knob ranges, the prices are very low so it's suitable for projects needing many controls so long as you don't need colour coded functions like on an audio mixer. I have seen these knobs on some pro-audio products such as microphone pre-amplifiers.
Rapid also have SCI ridged with metal cap knobs similar to what guitar effects makers call "Boss style" for similar money - I like those too.
