The .mdl (models), .wav (sounds), and .spr (sprites) files that replace the default 1.6 assets.
Since this is a community-made .rar file, it is always recommended to scan such archives for malware and verify the source, as mod packs are often distributed through community forums and file-sharing sites. AMX Mod X - CSGO Final Pack - Proyecto GoldSrc.rar
The .rar file likely contains a pre-configured setup. AMX Mod X is the industry-standard plugin system for GoldSrc servers. This specific pack likely includes: The .mdl (models)
Modified menus, kill feeds, and radars to match the CS:GO interface. AMX Mod X - CSGO Final Pack - Proyecto GoldSrc.rar