Switchable Stereo/Mono dual volume controls. Provides -19 db of ANR at average engine frequency band and -24 db of passive noise attenuation. Featuring the new Extend-O-Flex Microphone Boom and M-57 Electret mike. 9 Volt DC battery. Cellular phone ready (for ground use only). Three year Manufacturer's warranty. 14.1.9 oz.