SIMPLEX 4009-9201 IDNET NAC EXTENDER (New) The (120VAC) IDNet Notification Appliance Circuit Extender i s a self-contained adjunct panel. For use with Simplex Fire Alarm Control Panels. The base version of the 4009 IDNet NAC Extender i s a single-board system consisting of four NACs. A power supply, charger, an IDNet slave interface, and two conventional NAC inputs for hardwired control. Not applicable to the 4009 IDNet as an IDNet device.