Made in the U.S.A, the Maxi-Sound Digital features micro-miniaturized circuitry, integrated into a shell housing - smaller than the tip of your little finger. Comfortable and cosmetically discreet, there is nothing to wear behind the ear. MaxiSoundTM Digital Hearing Aids utilize state of the art Digital Signal Processing units, far more advance and producing clearer sound than older Analog hearing aid technology. FEATURES: Ambient Toggle Switch Allows wearer to switch from Full Range hearing for home or office, to ambient hearing, which filters the lower frequency (below 800 hertz). Microphone High Sensitivity microphone picks up sounds clearly and cleanly. Component housing contains state of the art amplifier with pre-set factory programmed Digital Signal Processor (DSP). Easy to install Type 312 Zinc Air batteries will last approximately 280 hours. The On/Off Volume Control is Easy to operate,The volume wheel offers a maximum output of over 116db. Factory Installed ear tip fits 90% of customers. You get 3 tip sizes to match any ear size, also includes a cleaning brush, carrying pouch/case, And 4 Batteries.