One of the top half dozen keyboards of all time. Beloved by all. Great sounding and immediately recognised when ever you hear it. As a stand alone keyboard, it sounds surprisingly awkward. When a clavinet player joins in with the band with a funky riff, people start to cheer.
I believe it was initially designed to be a classical instrument. Stevie Wonder used one and the rest, is, well, history.
The most popular model is the D6. There are a variety of different models. One combines the clavinet with the pianet. That's cool!
It runs off a 9v battery. The action and sound are based on the plucking of a reed. It sounds quite percussive.
Good ones are gold dust. Expect to pay a fortune for a D6. Other models tend to be slightly cheaper. All are rare and histerically sought after. Every synth from the M1 to Z1 have a program named 'clavinet'. Most sound quite good. It's an easy sound to sample or emulate. Not perfectly, but near enough.
Most 'one sound' keyboards become a cliche after a while. The clavinet certainly hasn't. It still sounds fresh and funky.