K55K Mercator

Developed in 1867 by Heinrich Kaufmann & Sons in Solingen. The original Mercator, or better known as the Black Cat K55K: "K" for Kaufmann, "55" for Hochstraße 55 (the original company address), and the final "K" for Katze—the cat emblem that was hand-painted on each knife. The novel, utilitarian design proved so essential that it quickly spread among factory workers, farmers, craftsmen, and eventually, American GIs who brought them home after World War II, where it gained cult status. This is the knife that defined what a working folder should be: slim enough to disappear in any pocket, substantial enough for the best of cutting tasks. The lockback mechanism represents early knife engineering at its most elegant: a curved spring bar that locks the blade open with positive engagement and releases with deliberate thumb pressure. The blade is made of carbon steel and maintains an exceptional edge.  Otter-Messer acquired the Mercator pattern from Kaufmann in 1995 and has maintained production standards established over 140 years ago.