The deeper you go, and slower you go, reducing noise is a must, but the coatings do work at 175+ depths. The snorkel coating seems to work pretty good, but you have to have the head set pretty close to the surface though, which makes it hard to travel in rough weather submerged with the snorkel up.
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A legislative act contrary to the Constitution is not law.
-John Marshall Chief Justice of the Supreme Court
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