The CHINA USB MODEM Composite Device is a generic name for a USB modem device that connects to a computer via USB, typically for internet connectivity (such as 3G, 4G, or dial-up modems). The term "composite device" refers to the fact that the modem may have multiple functionalities, such as a USB modem, a memory storage device, or a serial communication port, all grouped under a single USB device.

In some cases, the device might be identified with this generic name in Windows Device Manager if the proper driver is not installed or recognized automatically. This can happen with modems manufactured by companies in China or other regions, and they might not have specific drivers bundled with the device or may use a generic driver that Windows can recognize.