The Hot Wheels Silhouette is not an original Hot Wheels design. It was based on a custom built hot rod by Bill Cushenberry.
Of the original 16 Hot Wheels released, the Silhouette is usually one of the lowest valued cars. They were produced in higher numbers than the other originals, and finding one in good condition is relatively easy. The Silhouette is still a great model to start your redline collection with.