and the naming of his 1954 Stratocaster mechanical vibrato system as a "Tremolo Device for Stringed Instruments". Additionally, the 1956 Fender "Vibrolux" guitar amplifier, used electronically generated tremolo that Fender called "vibrato". Other classic guitar amplifiers contain electronic "vibrato units" that produce a tremolo effect via a tremolo circuit. Doc Kauffman's patent application for his "Vibrola" device (see below) already incorrectly spoke of "producing tremolo effects" in 1928. Other widely used names for the device include "vibrato bar" and "whammy bar", the latter attributed to guitarist Lonnie Mack's aggressive, rapid manipulation of the pitch-bending device in his 1963 song "Wham!" It has also been called a "whang bar". Designs Most vibrato systems for guitar are based on one of four basic designs: Bigsby Vibrato Tailpiece, introduced in the late 1940s and used in close to original form on many guitars (including Gibson, Gretsch and Rickenbacker guitars) Fender Synchronized Tremolo or strat trem, introduced on the Fender Stratocaster (1954), which inspired many designs, including: Floyd Rose locking tremolo (developed late 1970s) G&L Dual-fulcrum Vibrato, designed by Leo Fender (1981) Fender two-point synchronized tremolo (1986) Fender Floating Bridge, which has two main variants: Fender Floating Tremolo or jag trem, introduced on the Fender Jazzmaster (1958) Fender Dynamic Vibrato or stang trem, introduced on the Fender Mustang (1964) Cam-driven designs based on pedal steel guitar concepts, include: Kahler Tremolo System (1979) Washburn Wonderbar (1980s) Stetsbar tremolo (developed late 1980s) Many other designs exist in smaller numbers, notably several original designs marketed by Gibson under the Vibrola name, which they also used for some licensed Bigsby units. Kauffman Vibrola The world's first patented mechanical vibrato unit was created and designed by Doc Kauffman. The initial patent was filed in August 1929 and was officially published in 1932. Between 1920 and 1980 Kauffman collaborated with many pioneering guitar manufacturers including Rickenbacker, Gibson and Fender. In the late 1930s Rickenbacker produced the first commercial batch of electric Spanish guitars, utilizing the Kauffman "Vib-rol-a" as a stock option, thus setting precedence for electric guitars produced by Fender and Gibson. The Epiphone guitar company first offered the Vibrola as an option on some archtop guitars from 1935 to 1937. Epiphone sold the Vibrola as an aftermarket option as well. This Vibrola was also used on some Rickenbacker lap steel guitars at around the same time and was introduced on their six string 'Electro Spanish' guitars beginning about 1937.