All L.C. Smith's were on a Regular frame until 1907 when the 20 gauge came out on a Featherweight frame. Supposedly there were 7 20 gauges built on a Regular frame but as of now, not one has been reported. The joint check stopped in late 1889. The 3 position safety carried over from the Syracuse L.C. Smith's because the early Syracuse guns did not have that feature and for some live bird shooters and when trap shooting first started, calling for the bird and not shooting resulted in a lost bird and back then it usually meant money lost so the 3 position safety was put on Syracuse guns and that carried over to Hunter Arms Co. using that feature on their guns but was not a standard feature on later guns. Nitro Steel barrels were the best but there were some with Chain Damascus barrels.
The 3E shown has the last forend escutcheon after 1902, the banjo release, this is the 4th revision that lasted until the 1930's when the rectangular release was used.