OTF (Out The Front) Knives

OTF (Out The Front) Knives

Posted by Clayton on Dec 31st 2015

 OTF stands for “out-the-front.” The blade extends straight out. Instead of folding out from the sides, an OTF knife retracts and deploys from the front of the handle. Many people are under the mistaken impression these knives open up with deadly force. This is not the case. They merely open up quickly and efficiently.

The type of OTF knife you need depends on what you will do with it. Some criteria to use includes size, ease of opening, and whether or not you will carry it on your person or throw it in your toolbox.

There are four ways the blade can be aligned with the handle and locks in place. Manufacturers call these blades gravity knives, automatic switchblade, spring assisted knives, and manual sliding knives.

Gravity Knife


A gravity knife uses the force of gravity to open the blade. An advantage of these sorts of knives it that you only need one hand to lock the blade out. Gravity will do the rest. This type of knife became very popular with military parachute units to assist in cutting the parachute rigging away if the chute got tangled or they landed in trees or the water.

Today’s gravity knife often has a quick deployment feature whereby you use your thumb to rapidly get the blade out and in place (also called a sliding knife).


A good example of a gravity blade is the Microtech Combat Troodon OTF. This knife has an overall length of 9.5 inches with a 3.75-inch blade. It is stainless steel with an anodized aluminum handle. It even comes with a pocket clip and glass breaker. The thumb slide is double action, too.

Automatic Switch Blade

The classic switchblade, popularized in the movies, has been in use since the 1920s. The iconic photo of a juvenile delinquent in the 1950s usually included a teenager with a black leather jacket, slicked back hair, and a switchblade.

The blade of the knife is spring loaded and deploys as soon as you press a button. The handle is hollow, and longer and thicker than the blade. The spring actually holds the knife blade in, so once it is deployed you have to force it back into the handle and lock it in place again.

Automatic switchblades are illegal to import under Federal Law, one of the few Federal Laws governing the import weapons that are not firearms. Even though not all states outlaw switchblades, manufacturing them often is against the law. In addition, most states bar importing a switchblade from elsewhere. Hence, though not technically illegal, you effectively cannot own one in many locations.

Spring Assisted Knives

A spring-assisted knife has a lever, stud or flipper protrusion along the back spine of the knife. Pressing on the stud starts the blade deploying, and then they lock into place.


They can deploy quickly and are popular with emergency crews and firemen. However, even though they do not open automatically like a switchblade does, states like New York have passed laws against them.

Due to the spring assisted knives association with switch blades, manufacturers tend not to make many OTF knives that are spring assisted. Many of the spring assisted blades are folding. For example, Ken Onion designed the KS1550 Kershaw Blackout knife. It is a folding, spring assisted knife with a 3 3/8-inch blade. It is 4 3/8 inches long when closed (and also has a removable pocket clip).

Manual Sliding Knives

The most popular type of manual sliding knife is the box cutter or X-Actos. These knives have a button along the side that slides up and down the length of the handle. Many types of industries rely on these blades.

For example, carpet layers use manual sliding blades to cut carpet. In the workplace, these blades are often used to cut cardboard, open boxes, etc., and have become standard issue for workers in many industries.

3The Protech Emerson CQC7 has many of the features that most want in a manual sliding knife. Two of the most trusted names in knife manufacturing, Emerson and Pro Tech, have collaborated to produce the CQC7. It has a stainless steel bead blasted blade with an anodized aluminum handle. There is also a full knurl grip on the front and partial on the back. It has a slide safety to prevent accidental opening, a pocket clip, and comes with a nylon sheath.


An OTF knife has become one of the most, if not the most, popular kind of knife for everyday use. There is a wide variety of types and sizes available for daily use or collecting. They make great all-purpose knives to carry with you wherever you go.