Cleaning resin bands, suggestions

I clean my Casio resin strap in an ultrasonic cleaner. The watch itself does not go in the water, just the strap. Look at the picture in this link.

https://www.bobswatches.com/rolex-blog/watch-review/ultrasonic-cleaners-and-you.html

BTW, no soap needed in the ultrasonic. Just water is sufficient.

I must add that for the specific watch I just solved it with lukewarm water.

This model has easy to remove spring bars.

I'm impressed that after one year it is holding so well.

I also used a small drop of dishwash soap on the steel case back and a paper towel to absorb all humidity.

Thank you very much for the advice. 👍

For this one watch I solved it easily with lukewarm water, just posted pics and details in the tread.

I will keep in mind your suggestion for the future.

I wipe down my watches thoroughly after each wearing, with these microfiber towels:

As a result, I never have to "clean" my watches, as they always look absolutely pristine. 👍