Gun/Knife Contest Entry: Mercator k55k Review

Image courtesy Nemo

By Nemo

In the world of inexpensive knives, there are few more storied and lauded than the Opinel, the peasant knife par excellence, or the Douk Douk, which conjures images of Casablanca, Foreign Legionnaires in their white kepis, fragrant Moroccan souks, and hot desert sun, or from Germany, the Mercator k55k. All these knives were created around the same time, for the same purpose; to be a rugged, affordable and useful tool. Over 150 years later, these are still some of the most common knives one can find from the African Veldt to, Flanders fields, to the Rhur Valley, in the hands of the working man or soldier alike. They are still here and still common not because of their romance, but because they work, and they work well, even a century and a half after they were designed.

Image courtesy Nemo

The one that I have always loved the most was the k55k. They were first produced in 1867 by Heinrich Kauffmann and Sons, from Solingen Germany. The k55k motif stands for Kauffmann, no. 55, Cat, as evidenced by the famous leaping cat inlay. Intended as a general purpose knife for the soldier, they soon found nearly universal use in the Kaiser’s armies and colonies. They were never an issued item for the German Soldier, but through every war since 1867, the soldier in the know had one of these handy knives in his pocket or pack. After WWII, many Americans brought these Black Cat knives home as a war trophy, which was how they came to be known in the USA. Throughout the 50’s, they gained further fame as the weapon of choice for Bronx street toughs, which merely added to their already long and storied history.

Image courtesy Nemo
The design is the height of simplicity; a single piece of sheet steel is bent to form the body, rivets join the thin spear point blade and locking mechanism to the sheet. The locking mechanism is a spring loaded arm that protrudes from the body when the knife is open, and requires a firm thumb-press to release. This knife is thin, very thin compared to most modern folders. When closed, the thickness of the knife is a mere 6mm, and it sits in any pocket without bulge or discomfort. The blade is a spear point, 3mm thick at the spine, in your choice of Carbon or Stainless. These are working knives, they will cut gleefully and can be made as sharp as you would like to have them. I have been carrying a Carbon Steel model for 6 months now, and it has firmly and totally replaced my Swiss Army Knife for every task but opening wine bottles, and held up admirably to being used and abused. I like a knife I do not feel like I have to baby, and at around $30, its not hard to be okay with beating on this knife. In spite of the low price, the whole knife exudes that mysterious Solingen quality. Fit and finish is excellent, it has lovely heft in that hand, and has no flex in blade or body.

If you are a working man looking for a good utility blade, or just a average joe looking for an everyday knife with a little historical panache, you’d be hard pressed to find something better. And on top of that, everytime you take it out, someone will usually say “that’s a cool knife”.


  1. Sam L. says:

    Don’t know how my dad got it (I never knew he had it), but I found it after he died. I carry it occasionally. It was rusty, so sanded it off, sharpened and oiled it. It’s a cutter.

  2. RedRockRgr says:

    Looks a lot like the SOG Slim Jim XL without the history.

    1. Sock Monkey says:

      Thanks for the review. I’ve wanted one of those for a while. Can you recommend a good online vendor for them?

      (Sorry, didn’t mean this to be a reply to the last comment.)

    1. Sock Monkey says:


  3. Mark Davis says:

    Wow, this is a trip down nostalgia lane. The “Black Cat” was my first locking folder, back when I was kid living overseas. They’re great knives.

  4. Hammer says:

    I first saw one of these at the Apex Army Navy on Public Square in Watertown, NY back in the 70’s. It took a alot of pleading and good behavior to convince my father that I needed one. This brings back memories, looks like I will have to get another, Thanks.

Write a Comment

Your email address will not be published. Required fields are marked *

Gun/Knife Contest Entry: Mercator k55k Review

button to share on facebook
button to tweet
button to share via email