An unsupervised conference call allows two outside lines to be connected together in a trunk to trunk conference (no internal telephones).

• Step 1: While engaged in a conversation press the Conference Button or CONF Softkey (On your display).
• Step 2: Select an outside line or dial 9 and make the second call.
• Step 3: When the second call is answered press the Conference Button or CONF Softkey then press the green CALL Button.
• Step 4: Hang up.

Practice this before you try to transfer your biggest client to your boss!

You should also watch the 2 lines that are on the unsupervised conference to make sure they are released properly when the conference is terminated.  If the calls do not release you might need to call the phone company and have them add the Far-End Disconnect (disconnect supervision) feature to your telephone lines.