How to Use Blender's new ULTIMATE Shader: Principled — Blender Guru
Principled BSDF Shader Settings for Steel in Blender - Jigasu.Com
Principled Volume — Blender Manual
114956 - blender 4.0 : Transmission Roughness is missing in Principled BSDF, preventing some textures from being used correctly in previous versions - blender - Blender Projects
Principled Volume — Blender Manual
Here's a free Principled BSDF Shader guide to help Blender users, an extract from the free PDF guide and YouTube tutorial below, hope you find it useful :D : r/learnblender
Blender : Introduction au Principled BSDF - YouTube