This MB Quart PSAP-2 dual-input accessory plug works with your MB Quart GMR-1 or GMR-2 audio system, so you can access rear USB and 3.5mm jack inputs. The waterproof design enables installation on your boat or other outdoor vehicle.

MB Quart - Dual-Input Accessory Plug - Black

$14.99

This MB Quart PSAP-2 dual-input accessory plug works with your MB Quart GMR-1 or GMR-2 audio system, so you can access rear USB and 3.5mm jack inputs. The waterproof design enables installation on your boat or other outdoor vehicle.