The Microsoft Windows 8.1 Pro Pack License/Key is a standard operating system license pack that includes everything you need to upgrade your Windows operating system to version 8.1 Pro. It is designed for use on one device and requires a minimum of 2 GB of RAM, 1 GHz of processor speed, and 20 GB of hard drive space. The product is in English and is compatible with Windows operating systems. The license pack is from Microsoft, a trusted brand in the industry, and is manufactured in the United States.