Digicom 3G Router AM11 User Manual page 39

For source or destination port, you can define a single port (80) or a range of ports
(1000-1999). Add prefix "T" or "U" to specify TCP or UDP protocol. For example, T80, U53,
U2000-2999, No prefix indicates both TCP and UDP are defined. An empty implies all port
addresses. Packet Filter can work with Scheduling Rules, and give user more flexibility on
Access control. For Detail, please refer to Scheduling Rule.
Each rule can be enabled or disabled individually.
Click on "Save" to store your setting or "Undo" to give up