JBCSP3 Black 4" 8 Ohm 10-Watt Noise Canceling External Speaker capable of Talk back, PA (public address), includes 10' cord with 3.5 mm plug. Includes swivel mounting bracket with hardware included. Hear your CB radio better with an external speaker!, 4" 8 Ohm external speaker, 10 Watt , Noise Canceling, 10' cord with 3.5mm plug, Swivel mounting bracket and hardware included, To work properly, this product requires your radio to have both a PA jack and an external speaker jack., The red wire should be plugged into the PA jack. The black wire should be plugged into the external speaker jack., The talkback knob should be adjusted accordingly.