Features: CO. line 2-4 Ext. line 8-16 Multiple Communications Line normal transform power switch power (Optional) backup battary interface (Optional) Power Failure Transfer External Line Caller ID Transfer caller ID Intercom Caller ID Auto-Attendant(DISA-12s one paragraph) Outgoing Message Recording Auto IP Dialing Internal Music on holding Door Bell & Door Opener (Optional) Remote programming Memory protect while power off 11 chord melody music selectable Auto/Operator mode System Password Flexible Ext. No. Assignment Multiple Dial-Out Mode External line group Call Duration ControlCall Pickup Outgoing Call Transfer Call Transfer Call Forwarding Flexible coding(change Ext.No.) Do Not Disturb Automatic EX Reporting Flash Time Choice Ringing Assignment Call Restriction Three Way Conference C.O line transfer to C.O line Call all extensions Specific Co line dialing Ring identify C.O line Booking C.O line Reservation Operator setting CO Monitor