depends of what it isit always tell you where to unzip it on a txt or in the winrar archive, you just need to read
It's just a single RAR file though
You can follow it like a puzzle. If the zip contains materials\models, then put the contents in C:\...\team fortress 2\tf\materials\models.
But I don't know if a RAR file it a model or a script, I don't even know how to open it
Goddamnit why people are stupid enough not to use winRAR?