The USB Serial Port (PAX) driver is typically associated with a USB-to-serial communication device, often used for connecting various hardware (such as printers, barcode scanners, or certain industrial equipment) to a computer via USB. The PAX part of the name could refer to a specific manufacturer or device model, such as PAX Technology, which produces point-of-sale (POS) terminals and related hardware.

This driver enables the operating system to recognize and communicate with devices that use a serial communication protocol (RS-232, for example) over a USB port, allowing the computer to interact with the connected device as if it were using a traditional serial port.