Product Detail


  • Installs using single pair of wires
  • Operates two separate entryways
  • Distinctive ring for each entryway
  • Built in call-waiting






DoorBell Fon System

The 21st Century Door Answering System

This amazing product allows users to answer a door or gate from any telephone in their home or business.

It installs using a single pair of wires for (power, control, signaling & voice). All add-on component’s install on same single pair.

No Programming! No Codes! Just pick up the telephone like a regular telephone call.

National Security, Inc.
10410 Main Street
Fairfax, Virginia 22030

VA: 703-273-5555
MD: 301-656-6466
Loudoun Co: 703-771-1000
Toll Free: 800-886-0886
Fax: 703-273-0885