Knives for Self Defense

Automatic, OTF, and Assisted-Open — What’s the Difference?

All three types share the goal of fast one-hand deployment, but they work differently and have different legal statuses in some jurisdictions.

Automatic side-opening knives (sometimes called switchblades) deploy the blade outward to the side with a press of a button or lever. The blade swings open and locks in place. The 5-hole handle and solid handle models we carry both use this mechanism. These open fast and reliably, and both feature a safety lock that must be disengaged before the button will fire.

OTF (out-the-front) knives deploy the blade straight out through the front of the handle — the blade travels forward along the axis of the handle. The same button both extends and retracts the blade, which makes them compact and well-balanced in the hand. The double-edge OTF offers cutting capability in both directions; the single-edge is more practical for dual-purpose use. OTF knives tend to have a slimmer profile than side-opening automatics.

Assisted-open folding knives are not automatics — they require initial pressure on a thumb stud or flipper tab to start the opening motion, at which point an internal spring assists the blade to full open. They deploy nearly as fast as automatics but fall into a different legal category that is permitted in more states. The assisted-open folder we carry uses a 3Cr13 stainless blade rated for hard use with a belt clip for practical carry.

Blade Length and Legal Carry

Most states have knife carry laws tied to blade length, and 3.5 inches is a common threshold. Every defensive knife we carry uses a 3.5-inch blade or the 3.75-inch OTF double-edge, which falls within legal limits in a large majority of jurisdictions. That said, knife laws vary significantly by state and city, and some locations restrict automatic knives regardless of blade length.

Before carrying any knife in public, verify the laws in your state and municipality. Some cities — including New York City — have very strict rules about blade length and knife type that differ significantly from state law. We maintain a Laws & Restrictions page with state-by-state coverage.

The Case for a Disguised Knife as a Backup

The Comb Metal Knife and Plastic Brush Knife are not replacements for a primary defensive knife. They are lightweight, easily concealed backup options for situations where a visible knife would draw attention you don’t want to attract — travel, crowded environments, or locations where a visible knife might create unnecessary concern before any threat exists.

Both look and function as genuine grooming tools (the brush bristles and comb teeth are real). The Plastic Brush Knife adds a glass breaker tip, making it a multi-function tool. The blades on both are functional for defensive use in close quarters. If you carry a primary defensive knife, a disguised backup adds a second option accessible from a different pocket or position.

Carrying Your Knife for Quick Access

For any defensive knife to be useful, it must be accessible. The single most common carry mistake is keeping a defensive knife in a zipped pocket or buried at the bottom of a bag where retrieval under stress takes too long.

The belt clip on the Assisted Open Folding Pocket Knife is purpose-built for carry: the clip positions the knife at the waistband, grip up, ready for a one-handed draw. Automatic and OTF models without a belt clip are best carried in the front pants pocket with the handle oriented for a consistent draw. Practice your draw from wherever you carry — the deployment motion should be reflexive, not something you think through in the moment.