Introduced in the mid-1950s, the ZFK31/55 is a derivative of the K31 rifle configured for precision shooting with many of the parts changed towards that end. Approximately 4,150 were made with some being recently being imported into the United States. This model has a heavily reinforced blade front sight with integral flash hider/bayonet lug, with a tangent rear sight marked 1-15. These rifles feature a straight pull type action with the chamber area marked with the standard Swiss Cross inside a Shield. This model has the integral scope mounting points with the 3.5 sniper scope attached. The top of the scope body is marked "Kern Aarau/V=3.5x75" over 4245. These rifles were all fitted with a beech stock and handguard with a checkered pistol grip area with a sheet metal buttplate. The stock has a front folding sheet metal bipod and side mounted leather sling. This rifle includes a green painted metal belt carrier numbered to match the scope and one box magazine that is marked "Zf.Kar". The underside of the barrel is dot-matrix marked "ZFK31/55 SWISS 7.5MMX.55 OOW INC. CHARDON OH."

Very fine with 90% of the blue finish overall with wear on the exposed section of the barrel and receiver. The stock is in very good condition with handling marks and light pressure dent and dings on the underside of the stock from field use. The scope has 95% of the blue finish with clear optics. The scope can is also in very fine condition with 95% of the painted metal.