Ericophone

Better Homes and Gardents 1974.  Christmas Ideas.

It had a tweeter long before Twitter.  Made in North America by North Electric of Galion, Ohio, that company offered an optional "Ericotone" feature using a one-transistor oscillator to make a distinctive "chirping" sound, one of the first uses of a transistor in a telephone.

Designed in the late 1940's by the Ericsson Company of Sweden, it was the first commercially marketed telephone to incorporate the dial and handset into a single unit.

North American production of this phone was discontinued in 1972, so I suppose that ad above was for surplus devices.

The Wikipedia entry contains a long list of films and TV shows that featured people using Ericophones. Most recently, I saw one being used in the new remake of The Man From Uncle.

There's also an enthusiast's site where, among other things, you can purchase a refurbished, updated and functional Ericofon (the European spelling) that uses Bluetooth technology.  As the pitchman says, "Wouldn't (it) be great sitting at your favorite restaurant or coffee shop with an original Ericofon (Cobra), one of the most beautiful designed telephone of the 50's, and while working or talking with your friends this phone rings and it is a call for you?"  Only $600 US!  (Even with inflation, the original $60 price tag in 1974 would be worth only $307 today.)