This adapter cable features DB-9 (nine pin, D-Sub) and USB 2.0 Type A (four pin, 480Mbps) ends, and is designed to convert a USB 1.1 or 2.0 port into an RS232 Null Modem serial DB9 port to eliminate DCE/DTE conflicts directly Cable length of 1.7 meters (5.6 feet) offers plenty of reach, so you don’t have to move your gear around to accommodate Features COM retention, to allow the COM port value to be automatically reassigned if the cable is disconnected and reconnected, or if the system is rebooted Compatible with a variety of operating systems, including: Windows, Windows CE, Mac OS and Linux