G_s_SMHD_V2.06_256x.zip is a release file of the Minecraft resource pack G's Smooth Modern HD [256x], made for Minecraft 1.3.1. It was published on August 17, 2012 and is 146 MB in size. For the full description, screenshots and every other version, visit the G's Smooth Modern HD [256x] resource pack page.
How to install: Put the .zip into .minecraft/resourcepacks (do not extract it) and enable it under Options → Resource Packs.
