Sweeney,
The port on the side is high pressure as Hilditch indicated. The appliance you hook up will have to have a regulator on it. It must be this way since all gas appliances that use the 1lb bottles have a built in regulator. The side connection is only meant for gas appliances that use the 1lb bottle gas. The supplied connection hose is set up that way. If using a gas appliance that is meant to run off a larger tank you will need to create your own gas line adapter (sometimes the included reserve adapter does the trick) and make sure you have a regulator on the line.
Since most gas appliances have a regulator in the system already this should be fairly straight forward.
Cary