Fusion MS-NRX50 Single Stereo Volume Controller [010-04138-00]MS NRX50 Single Stereo Volume Controller Simple Audio Control This easy to use volume controller can be front mounted on your boats dash, and it controls all audio zones of a single stereo via a large single knob. Features: Large Single Knob Control Connects to your boat's NMEA 2000 Network Adjusts all audio zones of a single stereo Play or pause with the push of a button Requires single 1. 5" hole for installation IPX7 Rated for marine environments