This is the earliest ad I've found for the Morgan pad Mike; from January 16, 1932 "Sportsmen' Review"

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Morgan Adjustable Recoil Pad, 1932
Pat. No. 2,066,218 to W. J. Morgan issued Dec. 29, 1936 permits adjustment simultaneously both horizontally and vertically.
https://patents.google.com/patent/US1847777A/en

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and the Jenkins, made about 1930-1955. R.C. "Rock" Jenkins was President of the ATA, and the brothers had the Jenkins Brothers Gun Club, in Orleans, IN.

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