Don is correct in that the basic frames are the same. Weights will vary with earlier guns tending to the lighter side (though not always). My mid '30s, FW, 16ga., 26in is 6lbs. 8oz. with eng. style solid pad added to original stock length. My mid '20s, FWE, 20ga., 28in. is an identical weight with a pad. To my eye, the FW Smith and small frame Fox are both visually most balanced as 16s. Same goes for the M12.