• Designed for people with mild to severe hearing loss • Uses ClarityPower(TM) technology • Increases incoming sounds by up to 40dB • Adjustable tone control (600Hz-2.4kHz) amplifies specific frequency range for sound clarity & distinction between similar-sounding words like "chair" & "share" • Boost button allows for even more amplification & eliminates background noise & feedback by muting microphone in handset • Compatible with most home & office telephones where handset is separate from keypad • Easily connects between handset & phone base--no wiring involved • Compact & portable • Includes battery;