It is a "`tcpdump`(http://www.tcpdump.org/)" executable, WinPcap(http://www.winpcap.org/) library and driver wrapped in a simple executable that:

1. Unpacks the files to a temporary directory; 2. Installs and starts the "`npf`" driver (from WinPcap(http://www.winpcap.org/)); 3. Runs `tcpdump.exe`; and 4. Cleans up everything