Bigsby® Original Kalamazoo Series Vibratos are still Sand Cast by hand in the United States the old fashioned way. Molten Aluminum is poured into Sand Cast molds, exactly as Paul Bigsby made the original Bigsby Vibratos in the 1950s. We know how much your guitar means to you, and Bigsby Kalamazoo Series Vibrato systems are lovingly made to enhance your instrument while delivering Paul Bigsby’s original vision in every way.