Glossary
ContainerID
A GUID Windows gives to all device nodes that belong to the same physical device, linking Enum\USB, Enum\USBSTOR and SWD\WPDBUSENUM entries.
A USB stick appears as several device nodes: the USB device (Enum\USB\VID_…&PID_…), the disk (Enum\USBSTOR) and a portable-device view of its volume (Enum\SWD\WPDBUSENUM). Each has a ContainerID value, and they share the same GUID.
It is the link that still works when a device has a Windows-generated serial and the instance names differ. Internal devices share the all-zero / ffff root container, which must be ignored.