Call us killjoys, but we think it's never a good sign when a product description includes a boldfaced FBI warning immediately preceding an age recommendation of "4 and up." ("This device must not be used to make threatening phone calls!")
That's what the product literature says about this "Alien Voice Changer" from Atamaii Anime Toys. The gadget is so named because it makes you sound like extraterrestrial beings, according to Red Ferret--specifically, three aliens from Cartoon Networks' Ben 10: Greymatter, Heatblast and Fourarms. (What, no Stinkfly?)
The changer also comes with stickers so you can customize the mask that's included with it, presumably so you can really feel the character even while punking your friends over the phone. Lee Strasberg would have been so proud.