Assisted Opening Knives vs Switchblades: What’s the Difference?

What’s the difference between a switchblade and an assisted opening blade? Why is one illegal whereas the other is sold at every local knife store? Are automatic knives legal? These are three common questions knife enthusiasts, both new and experienced, commonly ask.

While the switchblade is generally reserved for law enforcement and military personnel, the exceedingly common assisted knife is readily available across most markets.

Spyderco Tenacious

Is it all in the name? When one thinks of a switchblade, one is instantly reminded of knife fights, gangs and stabbings. Is an assisted opening blade any different? Yes, and this article will help illustrate to you how they are similar, how they different, and why they are often on opposite sides of the law.

Below, take a look at the interactive table to compare some of the more popular pocket knives against one another:

Assisted Opening Blades

An assisted open knife is a folding knife that goes by many different names such as an AO Knife, Spring Assisted Knife, Quick Release, Quick Draw, and Semi-Auto Knife among others. All AO knives have one thing in common: they require you to start the process of opening them before springing open the rest of the way.

It is that fact that makes them popular, as unlike a traditional pocket knife, you do not have to open the blade manually the whole way, which makes it ideal for single hand deployment. For times you need a pocket knife–be it for opening boxes or cutting a rope–you do not want to spend a lot of time or energy trying to get the knife open. Instead, you simply want it to go from being in your pocket to usable as quickly as possible. This is exactly what the assisted opening mechanism was designed to do.

While not all assisted opening knives have locks on them, most do for the safety of the user. Many knives opt for a liner lock, where the lock itself is built into the scale liner. This makes for a very streamlined and easy to access lock, however, in knives with the lock on one side, it can create an issue for left-handed users as they usually are made with the right-handed user in mind.

Below, please take a moment to view some of the best-selling pocket knives currently for sale on Amazon:

1) Spyderco Tenacious
2) Kershaw Cryo II
3) Opinel No.7
4) Gerber Paraframe
5) Kershaw Knockout


A switchblade is defined as a pocket or EDC knife that opens with the press of a button. While this does carry a certain amount of “wow factor” and often a sleek and elegant design, this is what causes issues with many legal systems as it is felt that there are too many risks associated with this type of knife.

Switchblades can come in a manual version, which has a straight blade with an opening at the front of the knife, from which the blade is pushed out via a slide on the side of the knife. They also come in a spring loaded version which requires the user to simply press a button and the blade appears instantly, locking into position for whatever purpose it is needed.

Switchblades are rarely found with anything other than a plain or dagger edge, as a serrated edge is more likely to catch on the internal workings of the knife causing deployment issues.

Switchblades can have safety locks. However, a lot of them do not, which makes them very dangerous as any accidental press of the button will have the razor-sharp blade shooting out which can cause serious damage to the user or any child who may have been unfortunate enough to find said knife. This deployment method also causes an issue if the lock (should there be one) should fail or if the pin holding the blade back becomes worn.


There are quite a few similarities between a switchblade and an AO knife, as they are both portable blades, both have spring-loaded action to deploy the blade and they go from closed to usable almost instantly.


Despite the fact that a knife with an assisted opening mechanism is often confused with a switchblade, an AO blade differs in quite a few ways.

A switchblade has constant pressure being placed on the blade and is always waiting to be deployed with the only thing holding it closed is the locking mechanism. This differs from the assisted opening blade in that the spring does not apply pressure to the blade until it is past a certain point in which the spring takes over and finalizes the action. This is usually achieved either through jimping on the back of the blade which will give the required friction or a thumb stud mounted to the side of the blade.

Another difference is that with assisted blades, the knife always swings open from the side as opposed to a switchblade that can have a straight deployment.


To give a better look at these two types of knives, a simple look at one of each is provided below. The chosen knives are both the same brand and very similar to allow for a closer look at the differences rather than two completely unrelated blades.

  • Spyderco Embassy Black

The Spyderco Embassy Black is one of Spyderco’s restricted line of blades. These knives need to be special ordered through an ordering system and proof of qualifications must be provided to ensure those who do not possess the correct permits do not obtain this knife to comply with federal law.

Spyderco Embassy

This knife features a 3.125 inch blade, of which the full length is a usable cutting edge and comes in either a plain or combo edge. Made from CPM S30V steel and weighing a mere 3.6 oz, this knife screams Spyderco in its appearance complete with the hole on the back of the blade and three-position clip. Its overall length is 7.375 inches when deployed and 4.281 inches when closed, making this fit comfortably in the pocket when not in use yet remaining large enough to obtain a solid grip on the handle when in use.

The Embassy also features additional safety features to prevent accidental deployment. It has the required release button that all switchblades have, yet it also features a secondary safety switch to hold the blade firmly in the scales even if the button is accidently pressed.

Spyderco Manix 2 XL

The Spyderco Manix 2 XL is a tactical blade featuring a 3.85 inch blade with a 3.36 inch cutting edge and comes with a plain edge. The version being looked at is made with CPM S30V steel, although it also comes in 154CM and S90V steel although there is a price difference. As this blade has full steel liners it is quite heavy at 5.2 oz. and its appearance makes it instantly recognized as a Spyderco knife particularly with the oversized Spyderco Hole and oversized lanyard hole. When closed, this knife is 5.9 inches and stretches to an 8.94-inch length when fully open, making this slightly larger than your average pocket knife yet small enough that it does not require a specialized holder.

The locking mechanism on this knife is provided in the form of a ball bearing lock that allows you to disengage the blade without putting your fingers in the path of the blade.

One thing that some locks seem to have issues with is “spine whacking.” While the original Manix 2 did have issues with this, causing damage to the locking mechanism, Spyderco has resolved this issue with the Manix 2 XL making it suitable as the “hard use” knife it is marketed as.

Take a look at this video to see how successful the Manix 2 was in this particular spine whack test.

Things to note

As you can see, both knives are made of the same steel, have relatively similar blade lengths and even similar appearances. The differences are few and far between until it comes to the actual deployment of the knife, and that is the part that truly sets switchblades apart from assisted opening.

Switchblades do require additional safety measures and extra steps for purchase as opposed to an assisted open blade. This extra step is often either overlooked or purposely omitted from a lot of switchblades and therefore makes them much more prone to accidental deployment either in your pocket or in the hands of an unsuspecting child.


Overall, the differences between a switchblade and an AO blade are not known until you go to open the knife. Once you reach that point, the difference is obvious.

Switchblades, despite being an automatic opening knife, are generally no faster on the draw than a knife that features assisted open machinery. This makes one wonder what the true advantage to them is, as they are more likely to accidently deploy, cause more legal woes, and have locking issues as well.

Need more help? Head to our Reliable Knife homepage to find more great knife reviews!

You May Also Enjoy:

  1. Spyderco Tenacious review
  2. What’s the Best Kershaw Pocket Knife?
  3. Kershaw Ken Onion Blur review
  4. What are the Best Self Defense Knives?

Similar Posts

One Comment

Comments are closed.