Various Addons / Tools created by Rubat for the game Garry's Mod.
You do not need to download and install these manually, all of them are available on the Steam Workshop: http://steamcommunity.com/profiles/76561197996891752/myworkshopfiles/
Simply press the green + Subscribe button on the page of the addon you wish to install and it will be automatically downloaded when you next start Garry's Mod.