If you enter an IP as a rule there are also a few options. Please keep in mind that there can be different domains hosted on one server with the same IP.
126.96.36.199 will effect all connections to that IP. Regardless what the popup shows as a hostname.
Ranges are supported: 188.8.131.52-25 will effect all IPs within the range. Ranges are only supported for the last group.
129.168.2.* will effect all domains from 184.108.40.206 to 220.127.116.11