*Convert Any Phone into an Amplified Phone . . . Instantly!
*NEVER MISS AN IMPORTANT PHONE CALL MESSAGE AGAIN!"
*High Frequency Telephone Amplifier amplifies earpiece volume up to 3 times.
*Easy fingertip control.Compatible with standard and electronic phones, multi-line or single-line.
*On/Off switch so hearing and the hard-of-hearing can both use the same telephone.
*Easily installs between handset and phone base.