Left: Cone denim White oak.
Right: Japanese traditional cotton twill. Called Ichito Unsai.Mainly it used for Tabi socks.
I made a cap.
It is commercialized after feedback from about one year of sample trial.
As for what kind of fieldwork it is, if you don't wear something like this in the first place, you'll get sweat in your eyes. This is purely from the worker's point of view. When I started wearing glasses, I realized that I couldn't put a pencil in my ear. I want to use it as a substitute for gloves when I touch hot things, and I don't want to get holes in the iron powder of the sander, so I have to use cotton.
If the brim is too long, it's dangerous, so it's nice to have a shorter brim so you can wear a helmet over it.
Recommended for people who use pencils at work, technical mechanics and engineers.