The IP57 is a higher rating than the standard IP54 that helps provide first responders with high reliability in emergency situations. The number "5" stands for the dust intrusion rating or the capcaity to withstand the effects of fine abrasive dust particles. The "7" means a higher water intrusion rating.

The head of the microphone has been tested for 30 minutes of submersion at 1 meter but the connector is not similarly rated. This new remote speaker mic has the new Windporting feature that dramtically lessens background noise from high winds and other severe weather conditions. Audio can also pass through the speaker grill when blocked by water. This Microphone does NOT have a seperate audio jack located on the micophone. IF you want the one that does have it you need part number PMNN4021A. Hower it does not have the IP57 Rating.

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