OTF Blade Steels Explained: 440, 440C, D2 and AUS-8 in Out-the-Front Knives

By Best OTF Knives Editors. Updated September 12, 2026. Every pick was in stock at the listed price when this was updated.

Product pages for out-the-front knives list blade steel four ways: "steel" or "stainless steel" with no grade, 440 or 440C stainless, D2 tool steel, and AUS-8. In the $12 to $105 range those names tell you something real about edge holding and rust resistance, and nothing about whether the knife fires. This guide explains each, ranks them for the jobs an OTF actually does, and lists the in-stock knives that carry the named steels. All are on the OTF knives collection.

Quick comparison

How we ranked these

Every product on bestotfknives.com carries a 30-day order score recalculated daily from real orders across our store network. The picks below are the in-stock items with the highest score on the day of the last update, in that order, and each one is checked against its listed specifications. This is not a hands-on torture test and nothing here is sponsored; it is what buyers chose with their own money, explained.

The steels, plainly

Unnamed "steel" or "stainless steel." A 3Cr13 or 420-class stainless in practice: soft, easy to sharpen, rust-resistant, and it needs sharpening more often. This is most of the range under $35 and it is fine for opening boxes and cutting cord.

440 and 440C. 440C is the highest-carbon member of the 440 family and the best budget stainless: good edge holding for the price, good rust resistance, still easy to sharpen. Plain "440" without the letter is usually 440A or 440B, closer to the unnamed steels. Look for the C.

D2. A tool steel with high carbon and chromium just below the stainless line. It holds an edge noticeably longer than 440C and is harder to sharpen; it will spot-rust if left wet. On this site D2 appears on the G10-handled 9.75-inch knives and the Blackout Vector.

AUS-8. A Japanese stainless comparable to 440B with better toughness; takes a very sharp edge easily and holds it moderately. Eight knives in stock carry it.

Which matters for an OTF

Edge holding matters less on an OTF than on a work knife because most OTFs do light cutting, and the blade has to stay thin enough to travel through the front opening. Rust resistance matters more, because the blade lives inside a handle that collects pocket lint and moisture. That is why unnamed stainless and 440C are sensible defaults here, and why D2 knives need a wipe of oil. Sharpening: all four are hand-sharpenable; D2 takes the longest.

Knives with named steels

1. Blackout Vector Everyday OTF Knife - G10 Stealth Black

D2 on the best-selling large double action, 9.75 inches, about $48.

Double action means one slide does both jobs, deploy and retract. You never need a second hand to reset it, which matters if you cycle the knife often. Expect a slightly lighter spring than a single action of the same size.

A spear point keeps the dagger silhouette with a single sharpened edge, so it deploys as straight as a dagger and cuts better for everyday tasks.

Zinc alloy is the heavy, solid cast handle used across the $30 to $45 range. It adds weight in the hand and takes textured finishes well.

At 4-inch blade, 9.75 inches overall it sits in the full-size class, which makes it the full-grip class: a bag or belt knife rather than a pocket knife.

Best for: bag or belt carry and hard use, anyone who opens the knife often.

See current price and stock

2. Shadow Breach Double-Action OTF Knife - Black Alloy

440C on the value full-size double action, about $33.

The mechanism is double action, so the blade returns on the same slide that fires it. For a knife that gets opened many times a day this is the convenient choice, at the cost of a marginally softer deployment than a single action.

The dagger profile is symmetrical, which is why it is the most common OTF blade: it tracks straight through the front opening. It is a push-cutting and point-work shape rather than a slicer.

Zinc alloy is the heavy, solid cast handle used across the $30 to $45 range. It adds weight in the hand and takes textured finishes well.

At 3.25-inch blade, 8.75 inches overall it sits in the full-size class, which makes it the full-grip class: a bag or belt knife rather than a pocket knife.

Best for: bag or belt carry and hard use, anyone who opens the knife often.

See current price and stock

3. Shadow Ridge Tactical Response OTF Knife - G10 Black

D2 on a 4-inch serrated tanto with a G10-style handle, about $48.

The American tanto has a straight main edge and an angled secondary edge meeting at a reinforced point. It resists tip damage and suits push cuts and scraping; it is not a slicing shape.

G10-style laminate handles are the grippiest in the range and hold up to hard use; they are usually found on the tactical models.

At 4-inch blade, 9.75 inches overall, 4.64 ounces it sits in the full-size class, which makes it the full-grip class: a bag or belt knife rather than a pocket knife.

The edge is partially serrated near the handle. Serrations chew through rope and strapping and are harder to sharpen; buy plain edge if you maintain your own knives.

Best for: bag or belt carry and hard use.

See current price and stock

4. Stars & Stripes Double-Action OTF Knife - Green Flag

440C, 9-inch double-action dagger, about $40.

The mechanism is double action, so the blade returns on the same slide that fires it. For a knife that gets opened many times a day this is the convenient choice, at the cost of a marginally softer deployment than a single action.

The dagger profile is symmetrical, which is why it is the most common OTF blade: it tracks straight through the front opening. It is a push-cutting and point-work shape rather than a slicer.

Zinc alloy is the heavy, solid cast handle used across the $30 to $45 range. It adds weight in the hand and takes textured finishes well.

At 3.75-inch blade, 9 inches overall, 8.52 ounces it sits in the full-size class, which makes it the full-grip class: a bag or belt knife rather than a pocket knife.

Best for: bag or belt carry and hard use, anyone who opens the knife often.

See current price and stock

5. Blackline Breach Tactical OTF Knife - Midnight Black

440C, 9.45-inch double-action tanto, about $35.

Double action means one slide does both jobs, deploy and retract. You never need a second hand to reset it, which matters if you cycle the knife often. Expect a slightly lighter spring than a single action of the same size.

The American tanto has a straight main edge and an angled secondary edge meeting at a reinforced point. It resists tip damage and suits push cuts and scraping; it is not a slicing shape.

Zinc alloy is the heavy, solid cast handle used across the $30 to $45 range. It adds weight in the hand and takes textured finishes well.

At 4-inch blade, 9.45 inches overall it sits in the full-size class, which makes it the full-grip class: a bag or belt knife rather than a pocket knife.

Best for: bag or belt carry and hard use, anyone who opens the knife often.

See current price and stock

6. Heartline Quick-Draw OTF Knife - Red Hearts

440C on a $16 double-action mini, the cheapest named steel in stock.

This is a double-action model: the same slide fires the blade and pulls it back, so it closes one-handed. That is the feature daily carriers notice most, and it is why double actions take most of the top slots above $30.

A spear point keeps the dagger silhouette with a single sharpened edge, so it deploys as straight as a dagger and cuts better for everyday tasks.

Aluminum keeps the weight down and takes anodized colors, which is why most of the themed and mini models use it.

At 1.75-inch blade, 5.25 inches overall it sits in the mini class, which makes it a keychain or coin-pocket knife with a utility edge, not a work blade.

Best for: keychain and gift buyers, anyone who opens the knife often, a first purchase or a spare.

See current price and stock

7. Shadow Vector Duty OTF Dagger Knife - G10 Black

D2, 9.75-inch duty dagger, G10-style handle, about $48.

The dagger profile is symmetrical, which is why it is the most common OTF blade: it tracks straight through the front opening. It is a push-cutting and point-work shape rather than a slicer.

G10-style laminate handles are the grippiest in the range and hold up to hard use; they are usually found on the tactical models.

At 4-inch blade, 9.75 inches overall, 4.64 ounces it sits in the full-size class, which makes it the full-grip class: a bag or belt knife rather than a pocket knife.

Best for: bag or belt carry and hard use.

See current price and stock

8. Midnight Vector Tactical OTF Knife - G10 Black

D2, 9.75-inch tanto, G10-style handle, about $48.

The American tanto has a straight main edge and an angled secondary edge meeting at a reinforced point. It resists tip damage and suits push cuts and scraping; it is not a slicing shape.

G10-style laminate handles are the grippiest in the range and hold up to hard use; they are usually found on the tactical models.

At 4-inch blade, 9.75 inches overall, 4.64 ounces it sits in the full-size class, which makes it the full-grip class: a bag or belt knife rather than a pocket knife.

Best for: bag or belt carry and hard use.

See current price and stock

9. Desert Response Rapid-Deploy OTF Knife - Tan Zinc

440C, 8.75-inch double-action dagger in tan zinc, about $33.

Double action means one slide does both jobs, deploy and retract. You never need a second hand to reset it, which matters if you cycle the knife often. Expect a slightly lighter spring than a single action of the same size.

The dagger profile is symmetrical, which is why it is the most common OTF blade: it tracks straight through the front opening. It is a push-cutting and point-work shape rather than a slicer.

Zinc alloy is the heavy, solid cast handle used across the $30 to $45 range. It adds weight in the hand and takes textured finishes well.

At 3.25-inch blade, 8.75 inches overall it sits in the full-size class, which makes it the full-grip class: a bag or belt knife rather than a pocket knife.

Best for: bag or belt carry and hard use, anyone who opens the knife often.

See current price and stock

10. Greyline Resolve OTF Automatic Knife - Tactical Grey

440C, 8.75-inch dagger in tactical grey, about $33.

The dagger profile is symmetrical, which is why it is the most common OTF blade: it tracks straight through the front opening. It is a push-cutting and point-work shape rather than a slicer.

Zinc alloy is the heavy, solid cast handle used across the $30 to $45 range. It adds weight in the hand and takes textured finishes well.

At 3.25-inch blade, 8.75 inches overall it sits in the full-size class, which makes it the full-grip class: a bag or belt knife rather than a pocket knife.

Best for: bag or belt carry and hard use.

See current price and stock

11. Urban Lifeline Rapid-Deploy OTF Knife - Green Alloy

440C on the 8.75-inch double-action clip point, about $33. The best cutter with a named steel.

This is a double-action model: the same slide fires the blade and pulls it back, so it closes one-handed. That is the feature daily carriers notice most, and it is why double actions take most of the top slots above $30.

The clip point takes a section out of the spine near the tip for a finer point, with enough belly to slice. It is one of the few OTF shapes that cuts like an ordinary pocket knife.

Zinc alloy is the heavy, solid cast handle used across the $30 to $45 range. It adds weight in the hand and takes textured finishes well.

At 3.25-inch blade, 8.75 inches overall it sits in the full-size class, which makes it the full-grip class: a bag or belt knife rather than a pocket knife.

Best for: bag or belt carry and hard use, anyone who opens the knife often.

See current price and stock

12. Sandline Rapid-Deploy OTF Knife - Desert Tan G10

D2, 9.75-inch single-action spear point in desert tan G10-style, about $48.

It is single action: the switch fires the blade, and you reset it by pulling the blade back into the handle until it clicks. The trade for that two-handed reset is a stiffer spring and a harder, louder deployment.

A spear point keeps the dagger silhouette with a single sharpened edge, so it deploys as straight as a dagger and cuts better for everyday tasks.

G10-style laminate handles are the grippiest in the range and hold up to hard use; they are usually found on the tactical models.

At 4-inch blade, 9.75 inches overall it sits in the full-size class, which makes it the full-grip class: a bag or belt knife rather than a pocket knife.

Best for: bag or belt carry and hard use.

See current price and stock

13. Shadow Vector Compact OTF Dagger - Carbon Fiber Black

440 stainless on the best-selling double action on the site, about $35.

The mechanism is double action, so the blade returns on the same slide that fires it. For a knife that gets opened many times a day this is the convenient choice, at the cost of a marginally softer deployment than a single action.

The dagger profile is symmetrical, which is why it is the most common OTF blade: it tracks straight through the front opening. It is a push-cutting and point-work shape rather than a slicer.

The carbon fiber handle is the light option and shows texture under a clear coat; it does not change the mechanism, only the weight and grip.

At 3-inch blade, 7.25 inches overall it sits in the mid-size class, which makes it the everyday-carry class: enough blade to cut, small enough to forget in a pocket.

Best for: everyday carry with a clip, anyone who opens the knife often.

See current price and stock

Coated and Damascus-pattern blades

Black, blue, gold and rainbow finishes are coatings over one of the steels above; they add scratch resistance and wear at the edge with use. Damascus-pattern blades at this price are etched or coated stainless, not forged layered steel; see best Damascus OTF knives.

Frequently asked questions

What is the best steel for an OTF knife?

For this price range, 440C: a good balance of edge holding, rust resistance and easy sharpening. D2 if you want longer edge life and will oil the blade.

Is D2 better than 440C?

D2 holds an edge longer and is tougher; 440C resists rust better and sharpens faster. On a pocket OTF the difference is small.

Does blade steel affect how an OTF fires?

No. The mechanism, handle and springs decide that; steel decides edge life and rust.

Prices are the bestotfknives.com prices at the time of writing and change with stock. Automatic-knife rules differ by jurisdiction; before ordering, read the state-by-state automatic knife guide and check your local rules.