Serene Innovations HearAll Cell Phone Amplifier - Model SA-40Hear every word, even in noisy environments! With the HearAll Cell Phone Amplifier, you will hear every word, loud and clear. No more muffled words or straining to hear. Your caller's voice can be amplified up to 100 times louder (up to 40dB). Pairs to virtually any Bluetooth cell phone. Use as a handset or speakerphone. A visor clip is included for 'hands free' conversations in cars. Special T Coil Mode sends clear, crisp sound direct to your T Coil