The MultiVOIP 410-FX SIP gateway provides toll-free voice and fax communications over the Internet or Intranet. By integrating voice and fax into your existing data network, you can realize substantial savings on inter-office long distance toll charges. The MultiVOIP 410-FX gateway is available in 4-port model. It connects directly to phones, fax machines, key systems, PSTN lines, or a PBX to provide real-time, toll-quality voice connections to any office on your VOIP network. The MultiVOIP 410-FX gateway is designed to maximize the investments you've already made in your data and voice network infrastructure.