PBX-C503 provides a centralized solution for the communication needs of businesses. It supports 500 Users and 100 concurrent calls which is integrated voice, video, paging, fax, conference, recording and other useful functions. It's a truly powerful hardware platform and supports PSTN/GSM/WCDMA trunks, ISDNE1/T1 and BRI digital trunk lines. Through its innovative software features, it allows for enterprise-level unified VoIP communications.