Not sure what this gizmo actually is supposed to do, if you want to wet your mono before casting just tip water over spool?
Years ago, remember a company - maybe Kryston?? - brought out drops to put on mono to help long casting, err never seemed to catch on 😄
Myself and @greekskii have often had - 'words' - in the past, but for me not worth falling out over tbh 👍
I do have to agree with his comment:
I’m not sure I get the whole point of all this, but you cast line out and leave it in the water for hours on end. It’s well soaked up to the distance you’re casting anyway.