Using a VoIP telephone system offers you increased flexibility and the ability to rapidly expand when your business necessitates it. The full-color touch screen allows you to quickly and intuitively access the phone's features. VoIP technology allows you to make calls using your existing Internet connection. Accommodates up to 16 SIP accounts, so colleagues and coworkers can quickly make calls from your desk. Supports up to 6 expansion modules. USB 2.0 port allows you to attach a Bluetooth� or Wi-Fi dongle (sold separately) for increased connectivity options. 7" full-color touch screen has an 800 x 480 resolution, 24-bit color depth and is backlit for increased visibility. Caller ID shows the name, number and photo of incoming calls, while call waiting alerts you to incoming calls when the line is already engaged. Dual Gigabit Ethernet ports provide fast call handling. 1,000-entry phone book lets you quickly find the number you need. Headset port makes it easy to sync your existing headset for hands-free calling. RPS (Redirection and Provisioning Service) and Boot Mechanism, along with unified firmware and an Auto-P template, make it simple to deploy, maintain and upgrade the phone system. Backed by the manufacturer's 1-year limited warranty.