A voice changer can be really useful. You used to have to work to distort your voice when making prank calls, but now this little device does the trick. Use the "Own" setting to change your voice a little, or give it a whole different twist with either the "Monster" or "Alien" setting. With its deep, intimidating timbre, your Monster voice will make the person on the other end pale with fright. The Alien voice will make you sound like you just inhaled too much helium.
Of course you can use the Voice Changer under a mask as well as on the telephone. The Voice Changer has a holder for fastening it to your clothing, and the microphone has a clip for fastening it inside a face mask. Be sure to wear the microphone as close to your mouth as possible, otherwise your own voice might drown out the speaker.
The Voice Changer is approx. 13x7x2.5 cm (lxwxd) and does not include batteries (requires 3 AA batteries).