In-Line Noise Filter

Eliminate the engine whine noise from coming through your speakers with this simple item.

Comes with 4 holes for attachment to a flat surface.

• Blue wire is clean power (clean +)(or positive to the filtered device) and should connect to the radio / intercom red wire
• Black wire is ground (-) and should connect to the battery ground and the radio / intercom black ground wires
• Red wire is incoming hot (+ to the battery) and should be connected to the positive battery or positive terminal from the source power.

12 volt 12 Amp noise filter

See further instruction here or watch this example video here.