The Yealink SIP-T21P is a the perfect entry level SIP supported IP phone. The phone supports two validated VoIP or SIP accounts as the phone has two programmable buttons. The Yealink phone can be powered via any 802.3af compliant PoE switch, or the optional power supply. This Yealink phone also features a full duplex speakerphone and headset port for handsfree communication. The dual RJ45 Ethernet ports allow you to connect your phone and computer through a single network drop. Four soft keys along with the six navigation keys make configuring your Yealink SIP-T21P simple.