2 Blender files are included with this asset.  One has textures set to relative path and the other has the textures packed within the .blend file.

There are also .fbx, .obj, and files included if you need to use them in other programs, along with .png texture files within the .zip files.  Simply extract the .zip files into a folder and your ready to go. 

The Mix map is a packed channel map that has AO in the Red channel, Roughness in the Green channel and Metallic in the Blue channel to reduce files and file size in Blender.