I bought this from Amazon. I did not install because my telephone line was failing intermittently. The Veterans Administration gave me one because I am a disabled Veteran. Once the phone line was fixed, I hooked up the VA Captioned telephone.

Never hooked this one up. 

I did not know I was hard of hearing until I got the Captioned telephone. 

Hamilton CapTel 2400iSPNBT Captioned Telephone, Hearing Impaired Phones, Volume Control with up to 40dB Amplification Gain, Large Touch Screen Display, Wi-Fi Capable, Answering Machine & Speakerphone