OTF Automatic Knife – 3.5-Inch Blade, Belt Clip, Glass Breaker

Most people who carry a knife daily don’t need double-edge geometry. They need something that deploys quickly, sits reliably on a belt, and handles the actual cutting tasks that come up in a real day. The OTF Automatic Knife ST-AK-104 is built around that idea—a single-edge out-the-front automatic at 9 inches overall, with a 3.5-inch blade, a built-in belt clip, and a glass breaker tip on the handle base.

Who This Knife Is For

This knife fits people who’ve been curious about OTF deployment but found double-edge models more specialized than they needed. It works well for daily carriers who value consistent belt positioning, first responders and drivers who see the glass breaker as genuine utility rather than a novelty, and anyone transitioning from a traditional folder who wants a flat spine they can actually rest a finger on. If your knife is a tool first and everything else second, this configuration makes sense.

Is It the Right Fit for You?

Choose It If You Want

• Single-edge blade with a flat spine for controlled, precise cuts
• OTF deployment that works in tight spaces without requiring side clearance
• A belt clip that keeps the knife in a fixed, repeatable position
• A glass breaker tip integrated into a knife you’re already carrying

Consider Another Option If You Need

• Double-edge cutting geometry — a double-edge OTF is the better fit
• A lighter carry option — at 0.7 lbs, this is heavier than most folding knives
• Unrestricted carry everywhere — OTF automatics are restricted in a number of jurisdictions

OTF Automatic Knife ST-AK-104 Features and Benefits

• Out-the-front automatic deployment: The blade fires straight out the front with a single button press — fast, one-handed, and operable in confined spaces where a side-opening folder can’t swing clear.
• 3.5-inch single-edge blade: Long enough for practical cutting tasks, with a flat spine that lets you place a thumb or forefinger for control and precision during detailed work.
• Belt clip: Fixed positioning means you reach for the knife the same way every time. That consistency builds muscle memory and reduces fumbling when your hands are full or conditions are poor.
• Glass breaker tip: A hardened point on the handle base concentrates force on a small area of tempered glass — a straightforward addition for drivers, first responders, or anyone who spends time around vehicles.
• 9-inch overall length, 5.5-inch collapsed: Substantial enough to handle real tasks; the collapsed length keeps it manageable on a belt without feeling oversized.
• 0.7-lb weight: Heavier than a lightweight folder, which means this is a deliberate carry choice — not a knife you forget you have.
• Premium steel blade: Built for regular use rather than occasional display. The construction is consistent with a knife meant to be drawn, used, and re-deployed routinely.

How the OTF Automatic Knife ST-AK-104 Compares

Different carry configurations suit different needs. Here’s how this knife sits relative to two common alternatives.

Care and What’s Included

What’s in the Box

The OTF Automatic Knife ST-AK-104 ships with the knife itself. The belt clip is integrated into the handle and requires no separate attachment.

Care

Keep the blade clean and dry after use. Light oil on the blade and around the deployment mechanism will help maintain smooth function over time. Avoid submerging the knife — the internal slide mechanism benefits from staying free of debris and moisture.

Legal Notes

Automatic knives, including OTF models, are legal to own and carry in many US states, but a number of states, cities, and venues restrict or prohibit them. Buyers should verify local laws before purchasing or carrying. Laws in this area change, and what’s permitted in one location may not be in another.

OTF Automatic Knife ST-AK-104: Frequently Asked Questions

What makes the OTF Automatic Knife ST-AK-104 different from a double-edge OTF?

The ST-AK-104 has a single cutting edge with a flat spine on the back of the blade. That spine lets you rest a finger on it for more controlled, precise cuts — something a double-edge blade doesn’t allow. It’s a more familiar geometry for anyone coming from standard folding knives, and it makes the knife more practical for everyday cutting tasks.

How long is the blade on the OTF Automatic Knife ST-AK-104?

The blade is 3.5 inches. Overall length with the blade deployed is 9 inches. Collapsed length is 5.5 inches. The knife weighs 0.7 lbs. These dimensions put it in a category that’s substantial enough for real use while remaining manageable on a belt clip carry.

What does the glass breaker tip actually do?

It’s a hardened point built into the base of the handle. Tempered glass — the kind used in vehicle side windows — doesn’t shatter from broad pressure; it breaks when a hard point concentrates force on a small area. The glass breaker does that job without requiring a separate tool. For anyone who drives regularly or works around vehicles, it’s a straightforward addition to something they’re already carrying.

Is this knife legal to carry where I live?

OTF automatic knives are legal to own and carry in many US states, but restrictions are common at the state, city, and venue level. Some jurisdictions allow ownership but restrict carry in public. Because knife laws vary and change, check the specific rules for your location before buying or carrying the ST-AK-104.

Add This Knife to Your Daily Carry

The ST-AK-104 is a considered choice for carriers who want OTF deployment in a single-edge, belt-clip format. If the specs and configuration fit what you’re looking for, add it to your cart above. If you’re deciding between configurations, the comparison table above covers the main trade-offs.