You read most of the information available right there on the gun. "Acier" just means "Steel" in French. Bayard, the mounted knight, and Demi Bloc are trademarks of the manufacturer, Anciens Etablissments Pieper (1905-1957) in Herstal, Belgium. The 32 gauge shell had a diameter of .501 and length of 2.5 inches. 3 inch shells were also available but few guns were chambered for this length and no 32 gauge shells are available in the US. They may still be found in Europe, but will probably be called 14 MM instead of 32 gauge.