Grandstream UCM6301 IP PBX, 500 Users, 75 concurrent calls, 1хFXS, 1xFXO, 1xWAN, 1xLAN//Supports up to 3000 users and up to 450 concurrent callsZero configuration provisioning of Grandstream SIP endpointsBuilt-in conferencing & meetings platform; supports desktop, Wave app, and SIP endpointsWave for Android, iOS, Chrome and Firefox browsers allows communication with all UCM6300 users & solutionsAPI available for third-party integrations, including CRM and PMS platformsAdvanced security protection with secure boot, unique certificate and random default password to protect calls and accountsThree Gigabit auto-sensing RJ45 network ports with integrated PoE+ and support NAT routerAutomated NAT firewall traversal service facilitates secure remote connectionsSupports Full-Band Opus voice codec and H.264/H.263/ H.263+/H.265/VP8 video codec, jitter resilience up to 50% packet lossCompatible with GDMS for cloud setup, management and monitoringBased on Asterisk* version 16 open source telephony operating systemhttps://www.grandstream.com/products/ip-pbxs/ucm-series-ip-pbxs/product/ucm6300-series-ip-pbx