Hmm, I downloaded the file from cgtrader, which is "Unity_2018_2.6.rar".
I used 7-zip to extract the files: it gives me a single folder called "Turrel_and_Rover" which has "Materials" (empty), "Models", "Prefabs" and "Texture" subfolders.
Then I copied the "Turrel_and_Rover" folder into the "Assets" subfolder of my Unity (2019.2.1f1) project.
There are only two mat files in the rar "New Material 1" and "New Material", both of which are in the "Sci-fi Ship" folder.
I don't think the problem is 7-zip, I can open the rar in a hex editor and see that there are only these two mat files present.
It would be useful really if you're providing Unity stuff to have a demo scene, but I don't actually need that; I do need the materials though:)
Apologies again if I'm doing something stupid:)
We're also finding that (In Unity) the normal map doesn't seem to apply to both sides of the truck by default if we create our own materials - having the actual material files would presumably fix this?
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