There are limited 5 line phone system, it is rare and hard to find but it is very useful. Just like the Panasonic Kxtd7690 Panasonic Kx td7690 5 line Wireless Handset Panasonic Kxtd7690. With specific description and features: 5-line backlit LCD, 12 programmable CO line/feature functions, Speakerphone with auto answer, Navi-key operation, 2.5mm headset jack, Compatible with KX-TAW848 only, Requires KX-T0141 cell station.

Includes charger base and Li-Ion battery With contents: KX-TD7690 Multi-Cell Cordless Handset, Desk & Wall-Mountable Charger Base, Leather case, PBX Functionality Support: PBX system features can be connected and accessed with handset. Battery: High capacity, quick recharging Lithium Ion, Multi-System Registration: Up to 4 systems, Multi Cell Handover

Panasonic KX-TD7690: KX-TD7690 Multi-Cell Cordless Handset Panasonic. PBX Functionality Support: PBX system features can be accessed with handset. Battery: High capacity, quick recharging Lithium Ion. Multi-System Registration: Up to 4 systems. Multi Cell Handover. KX-TD7690 Multi-Cell Cordless Handset. Desk & Wall-Mountable Charger Base. Leather case 4.44" Height x 1.50" Width x 0.44" Depth 2.56 oz

It is no common because the 5 phone system is not glamorous, not high-tech, but still used by famous people just like David Letterman, government, law enforcement, business, education, and even the military. It has 5 line buttons plus a useful Hold button, mechanical ringer with a volume control, LED indicator lights. Refurbished, also with 90-day warranty. Modular handset cord. And line cord has 25-pair Amphenol type connector. Ringer is commonly or normally connected to yellow-slate wire pair for common-audible signaling on all telephone lines system. It can be re-connected to 1 individual line. A buzzer can be equipped and installed for intercom use, or to replace the tone or ringer.

There are vast option when it comes to telephones. A good example is the Cisco SPA525G 5-line IP Phone with Color Display: The Cisco SPA525G phone is usually connected to a network through its wired ethernet ports or it is connected by a built-in Wireless-G connection. For its wireless network connectivity, the Cisco SPA525G phone is supported with WPA and WEP security/encryption methods. The SPA525G can carefully and quickly identify available WiFI networks, and it can also store multiple AP profiles. The Cisco SPA525G also equipped and supports WiFi Protected Setup.

If a consumer is using the Wireless-G connection, a separate power supply adapter PA-100 is required. The Cisco SPA525G five and provides an additional Ethernet port that allows a computer to be attached and connected to the network through the IP Phone. Unlike traditional and standard phones, the Cisco SPA525G requires a separate power supply. Either connect a phone to an Ethernet switch that provides Power over Ethernet PoE, or us a separate power adapter PA-100.

Specific Features: 2 Ethernet 10/100Mbps ports, 802.3af Power Over Ethernet support, USB 2.0 host port for connecting a USB memory option device to play MP3 music files, AUX port (to attach a SPA932 attendant console), Bluetooth capability for headset support, 2.5mm stereo earphone jack for some wired headset, Wireless G client support, Kensington security slot support, Integrated web/XML applications (Weather, News, Sports, etc), Supports both SIP with SPA9000 or leading third party call control platforms and SPCP Protocols with Cisco Unified Communication 500 Series, One Year Warranty.

Another brand of 5 Line Phone System is the Telematrix TMX-508 5-Line Phone with specific features: Easy to Install, Advanced System Features, 5-Line System, Data Port, Headset Port, Volume Control, Redial, 20-Number Speed Dialing, Mute, Speaker, Hold, 8-Station Intercom, Operates During Power Outages. This gives consumers some choices when it comes to 5 Line Phone System.