The JL Audio MMR-5N2K MediaMaster NMEA 2000 Volume Controller is a wired remote designed to provide auxiliary volume control for compatible MediaMaster source units. It connects via NMEA 2000 using a Micro-C connector and supports both full network integration or direct connection to a single source unit. Built for harsh marine conditions, it features a rugged, weatherproof (IPX7-rated) construction ideal for outdoor use. Outfitted with an NMEA 2000 Micro-C connector, the MMR-5N2K connects to a host MediaMaster source unit in two ways:• Direct interface with a vessel's NMEA 2000 network using applicable NMEA 2000 cables and connectors (not included)• Direct connection to a single MediaMaster source unit using MMC-PN2K powered network cables (sold separately) to simulate an isolated, stand-alone NMEA 2000 networkNote: The MMR-5N2K should only be used with a single MediaMaster source unit, connected via a NMEA 2000 network or MMC-PN2K powered network cables (sold separately). The level control mode for each audio zone of the host source unit must be set to Relative or Variable. When connected, all audio zones will adjust simultaneously. Functionality of the MMR-5N2K is solely derived from the host MediaMaster source unit. The MMR-5N2K includes the following features: NMEA 2000 Certified (LEN 2)Weatherproof design (IPX7 rated) for real marine dutyLarge rotary design for easy adjustments, especially while in motionOne knob simultaneously adjusts all audio zones Simple, push-button audio mute/unmute controlIntegrated status LED ring with programmable brightnessFront-mounted design requires just a single 1.5-inch (38 mm) hole for installationAutomatically recognizes which MediaMaster source unit model is connectedThe MMR-5N2K is compatible with these MediaMaster source units: MM105MM100s-BEMM100sMM80-HRMM50 Connects via NMEA 2000 network or MMC-PN2K powered cables (sold separately) Weatherproof IPX7-rated design for durability in harsh marine & outdoor conditions Simple, reliable volume control for enhanced audio experience