One IP65 Stainless Steel Product. 2 options, with or without keypad. The on-board relay is activated from mobile phones and IP Telephones. With the Single Call Button option (none keypad) you set the Intercom to call a single pre-set extension number. If your systems allows you to form hunt groups, the call could potentially reach multiple phones. The 12-key keypad has several modes of calling out. Telephone mode, speed dial, call button and security PIN coded access. These devices are made for SIP and VoIP networks. However, for people not wanting to utilise VoIP, you can set up a simple Peer to Peer architecture. This is nothing more challenging than pairing up IP addresses. There are no limitation on distance. The paired IP POE endpoints just need to be sharing the same physical network.