3 Types of Opening Mechanisms and Popular Examples

Mar 12th 2019

So many people have a pocket knife and don’t pay attention to the opening or locking mechanisms used on them. One deploys the blade, the other offers safety, and both are important. The locking mechanism will likely be different between a manual opener and a spring assisted folding pocket knife, so here’s a brief overview to get you started.

   1. Assisted Opens

Assisted opens involve a spring or inner bar that requires the user to manually open the blade to a certain point, and then the mechanism takes over. These are not automatics as they do require a user to start opening it, so while you should check your local laws, these knives are generally legal and acceptable.


These are small metal studs located at the base of the knife, fully visible and accessible even when closed. It can take a bit of practice, getting your thumb in the right spot to flip it open. As these are spring assisted, they shouldn’t require any other effort than a bit of pressure to open the blade a little.


Flippers are operated using a bar shaped like a much like a shark’s fin that is on the back of the knife, near the blade. With a little finger pressure, the knife flips out and is ready to use.

This style is ambidextrous, and perfect for those with larger hands trying to open a smaller knife. Flippers are often used in conjunction with thumb studs.

   2. Manual Opens

Manual knives have no mechanism inside to spring the blade open. Everything is done by the user. Sometimes, these knives require two hands to open. These knives are much slower to deploy, which can be a problem in certain situations.

Manual knives are legal in most places, some cities or states have regulation limiting the length of the blade. Again, be sure to check your local laws before purchasing.

Nail Nick

This is a small groove in the side of the blade designed to hook your nail into. It requires two hands to open and is very slow. If you think you’ll be in a position where you’ll only have one hand free to open a knife, you should not choose this one. Many classic gentlemen’s knives are made with a nail nick.

Thumb Holes

Spyderco made the thumb hole famous. This allows you to open a manual knife with one hand, though it will probably take a good wrist flick as well to help it open more quickly. Still more acceptable in urban areas than a spring assisted, it’s also easier than a nail nick.

   3. Automatic Opens

The automatic knife opens with just the push of a button, which makes it dangerous to the user as well as the people around them. Like assisted opens, they are fast and easy to open one-handed and are fun to mess with.

However, since there are a number of legal issues surrounding this style of knife, we’d recommend steering clear of this one and buying a good spring assisted instead.

While you should always choose a knife that feels most comfortable to you, also take a look at your local and state laws to see what is legal for you to carry. If you have no real limitations, we recommend seeing if there’s a good spring assisted pocket knife for sale, but maybe that’s just us.