Polk Audio AA2652-A MM651UM 6.5-Inch Coax Ultra Marine Speaker
The MM Series speakers are considered an ultra-marine because they have passed the 600 hours of salt fog and UV testing of the ASTM international B117-03 and D4329-99 standards. Stainless steel heavy duty input terminals and mounting hardware are used to last and not corrode in marine environments. The completely sealed front design prevents water intrusion that would otherwise damage the speaker.
