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Demko Shark-Lock: What’s the Big Deal?


Andrew Demko has been one of the biggest names in knives for decades now. Many of the most popular Cold Steel knives are his designs. Heck, my favorite knife ever made, the Cold Steel AD-10, is a production version of his custom. A couple of years ago, Andrew Demko created Demko Knives, with the new and innovative Shark-Lock at the forefront of their knives. Today, I’m going to tell you everything you need to know about the Shark-Lock that has turned the knife industry on its head. 

What is the Shark-Lock? 

Credit: US Patent #10,632,632B1

The Shark-Lock is a spine-actuated locking mechanism for folding knives. Its most distinctive feature is its protrusion from the spine that kind of reminds the eye of a shark’s fin, hence its name. Not every lock that is actuated from the spine like this is a Shark-Lock. Under the hood, this lock has some significant differences from other locks, but we’ll talk about that more later. 

How strong is the Shark-Lock? 

The short answer is very, very, very strong. But before I give you the long answer, I have a bone to pick with you. 

I feel like asking “how strong is the Shark-Lock” is kind of like asking an orthopedic surgeon how much you have to bench to rupture your triceps tendon. We have answers, but they are useless to you. In the same way that you probably can’t bench enough to worry about your tendon, you probably can’t supply enough force to break a Shark-Lock. 

And since I know you’re curious, very few triceps tendons have ever been torn, and all recorded instances involved roided-up powerlifters and hilariously heavy weights. Don’t do drugs, kids. 

Andrew Demko up to his usual games, hanging weights from his knives until they break.

Some locks have a much lower break strength than the Shark-Lock. For example, the average adult could break the average liner lock with just their hands, although it wouldn’t be easy and would probably end in injury. But then there are locks like the crossbar lock, the lockback, the Tri-Ad Lock, the Shark-Lock, and many others that are far stronger than you could ever need them to be.  

But if you insist upon finding that absolute maximum-strength knife lock, you’re in luck. Andrew Demko is known for pushing his knives to the break point to prove his claims. He tested the little, 3.5 oz. AD20.5 to an absurd 875 inch-pounds of torque before breaking. With strength like that, you should worry more about breaking your blade than your lock. 

How does the Shark-Lock compare to the Tri-Ad Lock?

The strongest knife lock to date is the Tri-Ad Lock, also invented by Andrew Demko. The genius of that lock is also in the Shark-Lock – a sandwiched pin. Most knife locks interface directly with the blade, which puts all bending pressure on the lock itself. If you sandwich a pin between the lock and the blade, that all changes. The pin joins the lock in sharing the pressure, and that pin is bedded in the handle scales of the knife. This seriously levels up the strength of the knife. 

Notice how much further away from the pivot the lock pin on the Shark-Lock is than than the Tri-Ad Lock!

The Shark-Lock has a little more going on, though. Its pin is set back further than you’d think is necessary. The further back from the pivot the lockbar gets, the less mechanical advantage it has trying to break it. The tradeoff here is that elongating the tang of the blade makes for a large divot in the folded knife. The AD20.5 minimizes this by adding a guard, but it’s just a hallmark of the Shark Lock. 

All in all, the Shark Lock offers similar strength to the Tri-Ad lock, but offers it with a smooth, one-hand operable mechanism. It’s a great choice for all kinds of knives!

What knives have the Shark-Lock? 

The Shark-Lock is very new, so not too many knives have it just yet. Initially, only Demko custom AD20s had it. Every now and then we see some USA-made AD20s, but they always sell out so fast it almost breaks our website. Almost. 

But never fear, the Shark-Lock is also found on the Taiwanese-made Demko AD20.5 and Shark Cub. These knives take the design language of the original AD20 and trim it down to a more pocketable size and thickness. But don’t let that fool you, it’s still every bit as tough as you’d expect a Shark Lock to be.  


To date, the only non-Demko knife to feature the Shark-Lock is the Flytanium Arcade. This knife is fun because of how customizable it is. You can swap out the thumb studs, scales, and backspacers to add a ton of new flavor to it, all while keeping the rugged strength and one-hand usability of the Shark Lock. Another notable feature is its aluminum frame, which might make the knife stronger. 


But that’s it! We’ll see what other tricks Demko has up his sleeve in the future, but for now, this is the full Shark-Lock repertoire! 

Isn’t the Shark Lock just like a (fill in lock here)? Is it really all that original? 

To the outside observer, the Shark Lock does look similar to the Snecx SuperLock, the Sandrin Recoil Lock, the Cold Steel ATLAS Lock and others. These locks are all spine-actuated, but that’s about where the similarities end. 

The lock that drew the most comparison to the Shark-Lock was the SuperLock, designed by Snecx, a Malaysian knife genius. Knife nerds will wage digital warfare over these locks as though the SuperLock and the Shark-Lock were really trying to compete. The reality is that they are simply different mechanisms.  


For starters, the SuperLock is a fully open mechanism, and the entire lockbar can be pulled out without disassembly. Snecx is renowned for his customs that hold together with détentes and switches, requiring no tools to fully disassemble. His lock follows suit, even on his production designs. The Shark-Lock is threaded by two pins and requires full disassembly to clean. The SuperLock wedges between the tang of the blade and the stop pin, but the Shark-Lock introduces a third pin into the equation for locking purposes only.  

To make a long story short, they have similar user interfaces, but they’re functionally different. Both are great locks invented by renowned knifemakers. Both locks will serve you well. There is no need to type vitriol at strangers on the internet over this! 

Why Buy a Shark-Lock? 


When people talk about Demko locks, they’re usually talking about their extreme strength, giving your knife the absolute best chance of surviving hard use and abuse. This is great, but the Shark-Lock offers all of that same strength, just with a one-hand-operable and addictively fidgety action. So, if you’re looking for an EDC lock that will give you the same easy operation as many other knives, just with the strength of titans behind it, then the Shark-Lock might be the lock for you!