This is a DoorBell Fon System. It includes the Station Controller, Brass Door Station, Door Chime interface and manual. Works with either wired or wireless phone system in the house. Landline or VOIP, I’ve used it with both. Will not work if all you have is cellular phones, has to come to the base station or system by wire. There is no app for that. Works great, rings your phone with a distinctive ring, talk to who’s ever at the door through your phone. The brass is an upgraded door station, the cheaper ones are plastic. With the Door Chime interface it rings your regular door bell along with the phones. You can buy this on Amazon today for $305 or you can buy this one. Was in service and working flawlessly up until 12/15/16.

Here’s all the technical BS:

The Door Box Controller goes in-series with the telephone line coming into the house. Use it with or without a phone line!

Press the CALL button on the Door Box, and all of the phones in the house ring in a distinctive manner.

Built-in Call Waiting gives you a distinctive Beep. Hookflash to answer the door, and hookflash again to go back to your caller.

Call Waiting from the door works the same way as the Phone Company's, so your customer already knows how to use it!

The Door Chime Interface will ring a real door bell, or activate the switcher for a security camera.

Use the Door Strike Controller to open a door or gate. It goes in-series anywhere along the single pair to the door. If you have two doors, it only opens the door you're talking to when you press the * key on your telephone.

Call OUT to the door at any time if you hear noises outside. Simply hookflash to go between the phone line, Door 1, and Door 2.

Features:
• All the phones ring 3 times when a visitor pushes the "CALL" button... Just pick up the nearest phone to answer the call!

• 2 Door Boxes (Door 1 and Door 2) connect to the single Controller... It's unbelievably inexpensive to cover 2 or more Doors!

• Each Door has a Distinctive Ring if you are using the World's Best Door Box with a phone line.

• Set an answering machine on 2 rings to take messages from the Door and the phone line, or 4 rings to only take messages from the phone line.

• Full Duplex Operation to both Door Boxes - No Voice Switching, No Cutting In & Out!

• Only 1 Pair Needed to the Door! It even works on the old doorbell wire (18 gauge maximum size to go up to 350 feet, CAT5 will go up to 4,000 feet).

• Call OUT to the Door at any time... Flash to go between the Doors.

• The Door Box Controller will drive up to 5 standard ringers (5 REN, like the Phone Company), or a line on a phone system.

• Will work thousands of feet out to a Door Box at a Gate!

• No code to remember to open the door!   Press * and the optional Door Strike Controller buzzes your door for 3 seconds, or as long as you hold the * key, plus 3 seconds.

• For a stealth Door Box, mount a Door Box behind a grill above the door, and use the old door bell button as the CALL button. 

• Use the Door Chime Interface to operate a real doorbell, or to stop a security camera switcher on the correct camera for that door.