- Discreet compact design- Built-in microphone for silent monitoring- Automatic polling and programming software included- 2 Amp relay contacts for SL-2 strobe light control, etc.- SIP compliant (see DOD 944) for list of compatible phone systems and cloud providers- Outbound Proxy, Authentication ID, Peer to Peer, VLAN Tagging- PoE powered (class 1, <4 Watts)- Automatic Noise Canceling (ANC) feature for proper operation in noisy areas- VoIP eliminates the need for “Push to Talk” mode- Network downloadable firmware- Non-volatile digital voice announcer with 28 seconds of voice memory- Handsfree operation- Dials up to 5 emergency numbers- Cycles through backup phone numbers on busy or no-answer- Hangs up on busy signal, time-out or touch tone command- Extended temperature range (-40°F to 140°F)- Optional PB-100 Polling System available (DOD 232)- Optional SL-2 or BLK-4-EWP strobe light kit available (DOD 242/654)- Diagnostics for testing microphone, speaker, and relay- Also available with analog telecom interface, see PB-3 for more information (DOD 239)