Channel Configuration: As marked on the silver label (20CH / 16+4), it features 16 downstream (input/send) channels and 4 upstream (return) channels. The input ports are numbered 1 through 16, while the returns are labeled alphabetically (A through D).Length: It contains a 30-meter (approximately 100 feet) multi-core heavy-duty cable wrapped around the central spool.Connectors: The built-in hub uses standard 3-pin XLR chassis connectors to safely route multiple audio signals simultaneously between a live stage and a front-of-house (FOH) mixing console.