This option specifies which ports you want UDP datagrams to be sent to. It can be a single port, a comma-separated list of ports (e.g. 80,443,8080), a range (e.g. 1-1023), and any combination of those (e.g. 21-25,80,443,1024-2048). The beginning and/or end values of a range may be omitted, causing Nping to use 1 and 65535, respectively. So you can specify -p- to target ports from 1 through 65535. Using port zero is allowed if you specify it explicitly.

This option asks Nping to use the specified port as source port for the transmitted datagrams. Note that this might not work on all systems or may require root privileges. Specified value must be an integer in the range [0–65535].

Asks Nping to use an invalid UDP checksum for the packets sent to target hosts. Since virtually all host IP stacks properly drop these packets, any responses received are likely coming from a firewall or an IDS that didn't bother to verify the checksum. For more details on this technique, see http://nmap.org/p60-12.html.