$re = '/[0-9]{1,3}.[0-9]{1,3}.[0-9]{1,3}.[0-9]{1,3}:[0-9]{1,4}/m';
$str = 'Proxy: <Proxy US 0.19s [HTTPS] 20.206.106.192:80>';
preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0);
// Print the entire match result
var_dump($matches);
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for PHP, please visit: http://php.net/manual/en/ref.pcre.php