That's my understanding too, Joe. In looking for replacements for my 100ATR I discovered Mossberg has used at least 3 different triggers, the accutrigger on newer ones, and on older models, some have a nose for alignment and those are interchange with Howa and Vanguard, or others like mine have the same trigger except they use an alignment pin instead of the nose. They are the ones that are not available aftermarket. If I ever have to or want to replace my modified factory trigger, I would consider having a good machinist grind off the nose and drill the alignment hole. I don't think it would be that difficult for someone with the the skills and tools required to do it.