Vandal resistant SIP call station Two-way audio with Echo Cancel feature; Complies with SIP standard for easy integration in every SIP PBX. 316 grade stainless steel. 1 panic button; 1 reset button (on board). 2 input relays for alarm; 2 output relays for door opener. Water-proof & Dust-proof: IP65. PoE (IEEE802.3af, Power-over-Ethernet).