From EPC Standard
Noise reduction ear plugs are actually certainly not the same as noise cancellation Earplugs. The Direct sound Excessive Isolation Earplugs are actually much better classified as noise reduction Earplugs due to the fact that they do not make use of electronic devices to actively cancel ambient noise. Rather, the Direct Sound Earplugs actually block sound by demonstrating the audio out of your ears while enclosing your ears in copyrighted sound separating ear cups.
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