This nail polish insert is molded from sugarcane bagasse pulp, which is the fibre residue of those sugar factories. It is renewable with extensive sources. It is food safe.
This molded pulp packaging insert is made out of dry press. The top side is smooth and the underside is rough. The thickness is 2mm.

The cavities follow the product shapes and there are some "bumps" in the cavities to lock the products securely inside.