- Clarity in-line receiver amplifier- Increases incoming call volume up to 40dB (increases incoming volume up to 100 times) - Tone selector for maximum speech clarity (amplifies selective frequencies) - Connects between handset and phone base- Compatible with most home and office telephones with modular handset cords- Cannot be used with telephones with dialing pads in the handset- Turns on automatically when you lift the handset- Low battery indicator (red LED) - 9V battery included- Slide volume and slide tone controls- Boost button eliminates background noise and feedback for extra loud and clear conversations- WhiteCLARITYHA40