The Xcel 100 allows the wearer to select between four different listening modes Universal Speech Clarity High Frequency and Power Boost. The SoundActivated Compression and variable Dynamic Sound Suppression automatically adjusts compression time according to noise level intensity and duration instead of using conventional fixedtime" compression. The XCEL 100 also comes with programmable auto shutoff so forgetting to turn the muffs off and accidentally running down batteries is a thing of the past."