There are 42 in all. These are to replace tiles/icons on your computer such as the icon for your recycling bin and my documents. Once you replace the icons you CANNOT move the files or folder you have these in.
Instructions:
To use on Windows (I don't own a Mac, though these can be used on a Mac) right-click the regular folder you want and go to customize. Click "Change Icon". Find the one you want, click on it, then press "apply" or "ok". If you want to change a special folder like "My Computer" go to "Personalization" or "Display" in the control panel. Find where it says "Change Desktop Icons" and apply the icons you want.
Spoilers for Season 5 Episode 14
SampleDownload