Elvex Aware, Com-680, is a hearing protector with built-in stereo Am/Fm Radio, and Aware™ technology. The Aware technology allows you to listen to the environment and communicate with coworkers while listening to the radio. Com-680 provides Radio-reception on the FM-band between 88 and 108 MHz and on the AM-band between 520 and 1700 KHz, while still protecting your hearing in an efficient and comfortable way. Accessory jack for Com radios and MP3 players. A sensitive radio offers FM and AM reception, so that you may listen to music, your favorite sports team or talk radio show. Aware technology allows you to hear the environment and communicate with coworkers while listening to the radio or auxiliary devices. Com-680 uses two AA alkaline batteries (included) and they are replaceable through an external battery compartment. A fresh set of batteries provides about 150 hours of operation. Just in case you forget to turn off your radio headset, we have assured that you do not come back to a dead unit, by incorporating an automatic four-hour shutoff. The sound generated by the speakers is limited to a safe 82 dB level with the use of a gain limiter. Independent testing established a Noise Reduction Rating of 22 dB. Excellent sound quality: oversized speakers. Electronics in a protected compartments, separated from the ear cavity. Soft cushioned headband and replaceable ear cushions. Ergonomic placement of controls for easy adjustment even with gloved hands. Accessory jack/Input jack that allows connection of auxiliary devices, such as MP3 players, CD-players and communications radios. Device connected to the input jack, can be heard individually or at the same time as radio and Aware technology.