Valide trombone
The valide trombone is a valve-slide hybrid combination trombone invented by jazz musician Brad Gowans. The valide is a predecessor of the Superbone but is not the same instrument. The slide on the valide is at the inside of the valve configuration, and does not lock, requiring the player to hold the slide at all times and thus encouraging the player to use both the valve and the slide hands (versus the later Superbone, where the slide is to the outside of the valve configuration and does lock, meaning its use is optional and does not always  have to be held). The valide was most popularly manufactured by the Getzen Corporation in the 1940s and early 1950s, when its orchestra use waned. The last noted player of the valide trombone was Juan Tizol of the Duke Ellington and Harry James Orchestras.