I can hear what you're thinking. You're wondering whether netcat is really a good idea for this purpose. It isn't an encrypted tunnel with any authentication mechanism, and nc.exe is notoriously flagged by AV software. Well, we're running with netcat for now because it makes for a nice demonstration, but there is a practical purpose: I'm not sure there's anything quite as fast as this method for creating a persistent backdoor into a shell session on a Windows target. Nevertheless, you can leverage this method with any listener you like.