Designed for use with Scott full facepieces equipped with voicemitters as part of a complete respirator Amplifier electronically amplifies sound coming from the voicemitter Voice amplifier assembly is equipped with a green LED light on the top of the unit to indicate powe ON as well as low battery Features an automatic power OFF feature that shuts down power after 20 minutes of inactivity Instrinsically safe for use with commercially available alkaline and NiMH batteries Battery life of more than 50 hours is more than double that of the most popular models in the same market Ribbed, textured surface establishes more secure handling even with wet-gloved hands ON/OFF button with tactile surface makes it easy to recognize activation with a gloved hand Angled directional speaker projects an amplified voice in the direction the use if facing Upgradeable to include radio interface and talk-around, multi-channel functionality