Introduced in the mid-1950s, the ZFK31/55 is a derivative of the K31 rifle configured for precision long range shooting that is complete with its matching 3.5X sniper scope. There were approximately 4,150 manufactured circa 1955-58 with many recently being imported into the United States. These rifles feature a straight pull K-31 type action with the chamber area marked with the standard Swiss Cross inside a Shield. It is fitted with a slightly heavier tapered barrel with a heavy reinforced blade front sight with integral flash hider/bayonet lug. The tangent rear sight marked 1-15 (100-1500 meters). 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 4558. These rifles were all fitted with a beech hardwood stock and handguard with a checkered pistol grip area with a sheet metal buttplate. The stock has a front folding sheet metal bipod and a side mounted leather sling.

Excellent with 90% plus of the original matte blue finish overall showing wear on all the edges and high spots, with slightly more thinning on the exposed barrel section. The stock and handguard are both in excellent condition with minor handling marks and overall. The scope and mount retain 97% plus of their original blue finish with clear sharp optics.