Originally developed by Rheinmetall, the constraints of the Versailles Treaty forced them to go to Solothurn in Switzerland for production, with this example made in 1940. A heavy, machined steel beast of a weapon, contemporary reports list the S-18 as capable of 20mm penetration at 100 yards. While the armor trends of World War II eventually made it obsolete in the anti-tank role, they continued in use as aircraft armament, anti-aircraft guns, and in what is now known as the "anti-materiel" role, smashing up enemy vehicles and equipment. In addition to use by Nazi Germany, the S-18/1000 was also adopted by the Italians, seeing use on the African Front as armament for the L3/35 'tankette', as well as being used by the Italian Social Republic into the last days of the War in Europe. Fitted with a folding blade front and adjustable tangent rear sight, with a 5-port flash hider installed on the muzzle, the model marking and manufacture date on the chamber area, and an integral scope. A large crank with a rubberized handle serves as the cocking mechanism, with a hardwood grip and a thick, rubberized recoil pad is installed at the rear. In operation, the weapon is supported at the front with an adjustable bipod with integral traverse swivel, and at the rear with an elevation adjustable monopod. A green painted hardwood case is included; while stenciled with the nomenclature for a U.S. M39 20mm revolver cannon, the number on the case matches this lot. Also included are a canvas covered strap-on pad, a two-piece cleaning rod, and nine extra magazines.

Very fine, with 85% of the original blue finish, showing areas of nicely aged plum patina, bright edge wear and handling marks. Traces of what appears to be a two-tone green and brown camouflage paint job are present towards the rear of the barrel. The rubberized eye cup of the scope shows some folding and crushing, but is still present, and the optics are clear. The case shows mild wear and scuffing. Mechanically very good. NOTE: This Destructive Device is a National Firearms Act (NFA), fully transferable Class 3, which is registered with the Bureau of Alcohol, Tobacco, Firearms and Explosives, (BATFE) under the provisions of 18 U.S.C. Chapter 44 and 27 CFR part 478.