Gunmarks contains an extensive collection of trade marks, proof marks, and inspection symbols used by firearm manufacturers worldwide from approximately 1870 to the present. The marks are systematically organized by type and structure, including letter marks, monograms, figurative symbols, and geometric designs. Each mark is accompanied by contextual information about the corresponding manufacturer, often including model and caliber details. The second section of the book provides an alphabetical index of firearm manufacturers linked to their respective marks, making it a practical identification guide for collectors, historians, and dealers.