AV Access U2EX50 165-Feet Over Cat5e/6 USB 2.0 Extender. AV Access U2EX50 USB 2.0 extender is a slim transmitter (TX)receiver (RX) pair that can extend a USB signal up to 50m via Cat5e/6 cable. The built-in USB HUB in the RX supports up to 4 USB 2.0 ports.