Transparency on imported objects i downloaded an .obj file from the web. It shows an tank. The tracks of the tank has some transparent parts in the texture. But the mesh is always showing behind texture. I dont know how to remove them.

For better explain, here the images:





I mean the lightgrey parts. How can i remove them? Thank you for help and sorry for my worse english.

Cheers :)
Blender does not know the texture should be transparent on some parts.

If you're planning on using cycles, you can mix your shader with a transparent shader using a texture mask/alpha as the factor.