Telephone Handset Amplifier increases volume with the push of a button. Instantly increase handset volume for any hearing impaired individual. Great device for the elderly and easy to setup and use. Simply plugs into the handset of your telephone without any additional setup or programming. Handset amplifier uses 9volt battery that typically lasts 6-12 months depending on usage. Amplifier has a built in voice detection for on/off operation and saving battery life. Battery included with item.
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