"Hexatone" H5

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The H5 was the world's first five chime air horn. Developed by Robert Swanson (founder of AirChime) in 1949, only 88 H5's were made before the design was refined into the M5. The "H" stood for "hexatone," a carryover from Swanson's original multichime airhorn, the six-chime H6.

Original tuning was: A major dominant 7th (C#,E,G,A,C#),
but this could easily be changed to a number of other chords including F# minor 6th (C#,D#,F#,A,C#) and C# diminished (C#,E,G,A#,C#).

Only a few H5's are known to exist today in the hands of collectors.