by Clarity

• Compatible with home and most business phones (does not attach to phones with the keypad in the handset such as Princess, Trimline, or cordless phones)
• Volume adjustable up to 30 dB
• Separate tone control improves the clarity of the incoming voice
• Pushing the Boost button reduces background noise and provides an additional 10 decibels of amplification
• Runs on 9 volt battery (included)
• One year warranty
• For more information, click here to read the User Manual (PDF format)

Set-Up Tip:

• If the phone has a volume control, make sure it is turned all the way down or off
Troubleshooting Tips:
• A constant squealing sound is a sign that the HA-40 is not compatible with the phone. Make sure any volume control on the phone is turned down. If the squealing continues, return the HA-40.
• If other people can't hear the outgoing voice, this is a sign that the HA-40 is not compatible with the phone. Return the HA-40.