RadioWorks Product Detail David Clark MODEL H6040 Behind the Head Style (BTH) Features Specifications Documents 30 in. straight cord BTH style for applications requiring hard hats or protective headgear Flex boom for easy, precise microphone placement Foam-filled ear seals for maximum comfort Noise Reduction Rating (NRR): 23 dB Noise-shielded M-77 electret microphone for clear communication Rugged construction Noise Attenuation DataNRR23 dB Frequency (Hz) 125 250 500 1000 2000 3150 4000 6300 8000Attenuation (dB) 14.1 21.9 29.4 32.0 29.7 35.2 36.2 38.1 37.4Standard Deviation 2.5 2.5 3.0 2.7 2.2 1.7 2.5 2.9 2.8 Brochures6000 SERIES BROCHURE Are you ready to get to work? Get in touch and find out how RadioWorks can help your business. (800) 591-5525