This is a used / pre-loved item, we do our best to uphold the quality of all our used equipment.A single DS 4000 m Master Matrix is the heart of a simple ASL Digital Intercom system for up to 40 users. The conversation points are connected via five Intercom line outputs on the back. The connected cables can be configured as line, daisy chain or star topologies. Each intercom line contains the data for a maximum of eight user stations. The Intercom Line starting connections also deliver +48 VDC via the CAT-5 cable;This voltage is for Beltpacks and smaller speeches that do not have their own power supply.