POP3S (POP3-over-SSL/TLS) – port 995

Netcat

nc -nv x.x.x.x 995
or
openssl s_client -connect x.x.x.x:995
or
openssl s_client -crlf -connect x.x.x.x:995 -starttls pop3

# didn't work
USER username
PASS password

LIST – lists the messages available in the user’s account, returning a status message and list with each row containing a message number and the size of that message in bytes
STAT – returns a status message, the number of messages in the mailbox, and the size of the mailbox in bytes
RETR [message_num] – returns the message identified by the message number, which is the same as the message number shown in the LIST command output
TOP [message_num] [n] – returns the top n lines of the message denoted by message number.
When finished, the QUIT command will end the session.