I didn't mention any of the others because the correspondent said Belgium. There are others including National Arms Co, a maker located in Baltimore,D from 1898 to 1899; National Arms Co, a dealer located in New Orleans,LA from 1918 to 1920; National Arms Arms Co, name used by Crescent Fire Arms on both doubles and singles and Marlin Firearms on slide action guns; National Arms Co-R. Murdock, used by Hopkins & Allen on single guns; National Arms & Ammunition, an English maker from 1873 to 1896; National Fire Arms Co, used by Marlin Firearms Co on Model 20 shotguns; National Firearms, marking found on 8 gauge Martini type single gun with an 1887 patent date. Possibly made by National Arms & Ammunition and National Gun Company, a gun maker located in Baltimore,MD 1897 to 1898. One has to be careful when asking about some old "Trade Brand Name" shotgun giving the name and markings just as they appear on the gun with no additions, deletions and contractions. As far as I know Crescent did not make shotguns using Belgian made barrels. They and their parent company H & D Folsome did import many whole guns made entirely in Belgium.