Designed for people with mild to severe hearing loss<br> Increases incoming sounds by up to 40dB<br> Adjustable tone control amplifies specific <br>frequency range for sound clarity & distinction <br>between similar-sounding words like "<br>chair"<br> & "<br>share"<br><br> Compatible with most home & office telephones<br> Connects easily between handset & phone base--no wiring involved<br> Compact & portable<br> Includes battery<br>