Aastra 9133i SIP IP Telephone (A1720-0131-10-05) - is an advanced, fully featured multi-line IP Telephone that takes full advantage of VoIP technology by offering a flexible, interoperable solution at an affordable price. 3 line adjustable backlit display. 7 programmable keys. 4 navigational keys. Up to 9 call appearance lines. Personal directory. 10 predefined hard keys including Conference, Call Transfer, Redial, Options, Directory, Save, Delete, Speaker/Headset, Mute. Enhanced Call Management — Large storage for personal directory, callers log, and redial list. Tight Integration — Support for multiple IP telephony systems including BroadWorks®, Nortel, Sylantro, and Asterisk SIP. Built-in HTTP server for web administration and maintenance. Multiple Line/Call Appearance Lights — Support up to 9 simultaneous calls. Juggle multiple calls easily with a single press of a button. Shared Call Appearances — Shared calls allow you to place a call on hold at one set and pick it up easily at another set. Remarkable Audio — Quality speakerphone with excellent voice clarity and delivery. Protect Your Investments — Firmware upgrades can be downloaded and installed in the field as standards develop and protocols evolve. Less Wiring — Built in dual 10/100 switched Ethernet ports let you share a connection with your computer. Inline power upport eliminates the need for a power adapter. Compatible with IEEE 802.3af inline power device. Hearing aid compatible handset. Feature availability dependent on IP telephony systems.