Detail this asset from Unity Store: Original Link
This is a paid asset, but now you can download City Nature Takeover Free.
City Nature Takeover v1.3 (Latest version)
High environment pack.
A nice and big package that contains a lot of detailed assets, perfect for making roof environment. All objects have a prefab with their own material. Objects are all very low poly and optimized.
This pack contains:
57 detailed objects.
Textures maps for each object:
Gloss map ( in alpha of specular ).
All maps are 1024×1024 or lower.