GRANDSTREAM | UCM6301 IP PBXMade in Boston, MA USA. The Grandstream UCM6301 is an easy to manage device that does not require licensing fees and can support up to 50 users and up to 15 concurrent calls. It features advanced technology including three Gigabit auto sensing RJ45 network ports with integrated PoE+ and support for a NAT router. This enterprise grade IP PBX can be integrated with third party CRMs and PMS allowing for custom integrations.