The Logilink CF2091S is a network cable tester designed for testing RJ45, BNC and USB cables. The tester features a 2.4 inch LCD display with a touch-screen interface, making it easy to use. It can detect and display the port number, wiring sequence, cable length, and whether or not there is a connection between the two ports. It can also test across shielded and unshielded cables, and trace the signal path of a cable. It is powered by a 9V battery and comes with a carrying case for portability.