The quality of this model is very good. It plugs into your phone so you do not have to hold it over the handset mouthpiece. Pitch can be adjusted to make for voice sound low or high. Great for practical jokes or for women when home alone. Installs in seconds by plugging into the handset and base of any single line phone. Will not work on multiline phone systems.The quality of this model is very good. It plugs into your phone so you do not have to hold it over the handset mouthpiece. Pitch can be adjusted to make for voice sound low or high. Great for practical jokes or for women when home alone. Installs in seconds by plugging into the handset and base of any single line phone. Will not work on multiline phone systems.