The inserts are great, I'm thrilled. In one barefoot brand sandal, my son has inserts that slip and bunch up in the front when he puts them on. So I was looking for a replacement and found these. They fit perfectly, I just shortened them a bit in the back. The bottom layer doesn't slip and also makes my feet sweat less, the top layer is linen. The thickness is 3 mm and they are soft flexible.

I like
They don't slip Size corresponds No sweating in them Ideal for bf shoes