EC2: How to add port 8080 in security group?

I want to add port 8080 to EC2 security group to access tomcat. But whenever I select HTTP from drop down I get 80 port as default and also can't change it.

So how can I add 8080 so that I can access Tomcat publicly?

You have to choose "Custom TCP rule" in the dropdown.

Then you will be able to change the port to 8080.