I'm 99% certain I have seen Trojan Grade 12ga with rib extension. While I did not read what was on the rib I do remember unrounded angular shaping of the action. It was very good shotgun that goes largely unappreciated. Nice all original sample with some honest wear, but in excellent mechanical order can be had for just north of 1,000. It is kind of surprising because production numbers of Trojan grade are only few thousand higher than those of Winchester Model 21. Interestingly if I remember my measurements correctly action flats on Parker are longer than those of Model 21. Anyhow the Trojan is a "work horse" of a shotgun.