From the TRaK2 Texture set By Georges "TRaK" Grondin

Some source textures are copyrighted by CGTextures.com. Permission to use these specific textures under the GPL/CC-BY-SA as been granted to the author of this texture pack. Textures downloaded from CGTextures.com do not fall under the GPL/CC-BY-SA by default.

If you wish to use these textures under a license other than the GPL or CC-by-SA, please contact TRaK. Enjoy :)