This is the industry open-source standard. Every texture is royalty-free and CC0 (Creative Commons Zero).
Downloading the files is only half the battle. Here is how to install your free V-Ray material library for 3ds Max 2020 correctly so you don't end up with pink textures. vray material library for 3ds max 2020 free download best
If you downloaded a library from a third-party site (like a collection of .max files or .mat libraries), here is how to install it for quick access in 3ds Max 2020: This is the industry open-source standard
Arroway is a premium texture brand, but they offer 15+ high-resolution tileable textures for free. These are not .vismat files, but standard bitmaps. Downloading the files is only half the battle