Cavity plugs

2 ports, all ports blocked

2 ports, all ports open

2 ports, port 1 open to external port, port 2 blocked

2 ports, port 2 open to external port, port 1 blocked

3 ports, all ports blocked

3 ports, all ports open

3 ports, port 1 open to external port, ports 2 and 3 blocked

3 ports, port 1+2 open to external port, and 3 blocked

3 ports, ports 1 to 2 open, port 3 blocked

3 ports, ports 1 to 3 open, port 2 blocked

3 ports, ports 2 to 3 open, port 1 blocked

4 ports, all ports blocked

4 ports, all ports open

4 ports, all ports blocked

4 ports, all ports open

4 ports, ports 1 to 2 open, ports 3 and 4 blocked

4 ports, ports 1 to 3 open, ports 2 and 4 blocked

4 ports, ports 1 to 2 open, ports 3 to 4 open

4 ports, ports 1 to 4 open, ports 2 to 3 open

6 ports, all ports blocked

6 ports, all ports open

6 ports, ports 1, 2, 3 and 4 open, ports 5 and 6 blocked