One of the things I appreciate most about the knife community is the relentless drive for innovation and originality. Sure, I enjoy diving into the subtle tweaks on the latest flippers, but it’s the truly revolutionary designs that leave me in awe.
For a tool that’s been around for millions of years, the knife continues to evolve in exciting and unexpected ways. These bold designs might be hit-or-miss—and many don’t stick around—but they’re proof that no matter how long something’s been around, there’s always room for fresh thinking and creative breakthroughs.
Here are 15 knives with the most interesting deployment mechanisms.
1. Kershaw ET

Let’s kick things off with a knife that almost always comes up when you talk about unique opening mechanisms: the Kershaw ET. Short for External Toggle, the ET was the brainchild of the inventive duo Grant and Gavin Hawk. This father-and-son team is known for their outside-the-box creations, including the TOAD, Boker Griploc, and several others.
The Kershaw ET features a toggle mechanism that lets you open and close the blade in a few different ways. While you can operate it like a traditional folder (using your thumb and dropping the handle while holding the blade) the toggle mechanism is easily the most fun. A lever near the butt of the handle lets you control the action. Unfortunately, the knife was discontinued, likely due to the risk of it accidentally closing on your thumb when using the toggle.
Here’s a gif of how it opens with the toggle from this review:

2. CRKT Rollock

Next, we have another discontinued knife: the CRKT Rollock. What makes this one stand out is its unique opening mechanism. To deploy the blade, you press down on some jimping near the back of the spine while it’s closed. This action causes the blade to pop up, allowing you to slide it fully open.
This production model from CRKT was based on the original Rolox design by Blackie Collins. Collins is frequently credited as the pioneer of the assisted-opening knife, although Ken Onion may have developed the SpeedSafe mechanism around the same time.
Here’s a gif from an old YouTube :

3. Paragon Knives by Asheville Steel Warlock

The Warlock from Paragon Knives by Asheville Steel (yeah, it’s a bit of a mouthful) doesn’t fit neatly into the automatic or assisted opening categories—it carves out a space of its own. When closed, the blade is completely hidden from view. So how do you bring this thing to life?
Continue reading