I don't know. I'm more used to model numbers being a bit more definitive, while part numbers appear differently they are using the same model number on different tools. Having a model number for a particular tool would require a separate way to further identify which tool it is, which might be their system. It may be just a small sequence of their alpha numeric system of cataloging.
Are they using the same model number for the group of tools that are used to assemble the shotguns identified? That would explain the model number designation, along with the part number.
"Having a model number for a particular tool would require a separate way to further identify which tool it is, which might be their system" That would be done using the part number.
R.



















































