Designed to be fired at much longer distances than standard shotguns of the day, the Super Fox was a major step forward in shotgun choke boring. Per page 229 of Michael McIntosh's "A. H. Fox: The Finest Gun in the World" only a total of 300 Super-Fox guns are believed to have been built, approximately 240 of which were chambered in 12 gauge, and fewer still with factory 3" chambers as seen on this example, making this quite a rare gun. The two included J. T. Callahan letters both confirm the gun's HE Grade, gauge, chokes, and chambers when it was shipped from the factory on January 19, 1925. Chambers measured 3" with ejectors, chokes measured full/full, and 14 1/2" LOP.