There must be just one with/without a camera main unit in every installation. The main unit installation requires two frame/box positions; the other position however is left for additional module installation. Available also in black.The AXIS IP Verso security intercom is configurable to your needs thanks to its modularity. It provides reliable access control and allows you to easily interface with other systems. Adjustable door security levels Intuitive controls and search SIP communication protocol Security relay AXIS Remote Configuration Picture to email Integrates within a LAN WAN Web Ethernet network system Integration with third-party CCTV systems with ONVIF support Power over Ethernet PoE or 12v power supply Stylish discreet design; robust materials and construction IP54 protection rating