FAT

The File Allocation Table (FAT) filesystem was originally created for use with MS-DOS (and later pre-NT Microsoft Windows); currently a late version of FAT (FAT32) is used for USB flash disks. It has made its way over to Linux systems and has official support in the Linux kernel.

Emerge
The package is needed for FAT userspace utilities:

Usage
It should be possible to mount FAT filesystems with the command.