I have found a shemagh a vital addition to my kit. Essentially it's a 42 inch square of check-patterned cloth, as worn by Arabs.
It can be wrapped (generally rather briefly) around my face in the event I feel obligated to wear a 'face covering'. The effect is more ISIL Reject than Lawrence of Arabia, but never mind. It is almost certainly equally useless as other cloth masks, but somewhat more breathable.
If I stretch one corner across the crown of my head, I can then twist the tail and coil it around, creating a sort of sun hat. If the coil is wetted, there's a decent cooling effect.
It doubles as a foot towel after river crossings. I do not think that anything in a beach river is half as noxious as the mix of snot and saliva that contaminates face masks so I have few qualms about using it on my face after my feet.
I think it might be useful in the case of beach sandstorms, but these are rare and I haven't had chance to test it. This chap has found even more uses
https://expertvagabond.com/shemagh-keffiyeh/All in all £6 well spent on Amazon.