Chattervox 100 Voice Speech Amplifier with Headset The Chattervox is a compact personal amplification system that provides up to 15dB of a voice boost for mild to moderate speech impairments. Simple to operate with only one user control: the combined volume control/power switch. An affordable solution for people with low-volume speech. Size: 8" W x 2.9" H x 2.1" D Weight: 355 gm (.78 lbs.) Power requirements: 9VDC Nominal gain before feedback: 15dB Max power output: 5W Min (at 4 ohms speaker load) Six AA NiMH rechargeable batteries Entire system can be recharged overnight. (Option of using simple AA battery cells if rechargeables are insufficient; no expensive custom battery pack is required).