Benchmade H2O Fixed Blade Dive Knife 112SBK-BLK

Benchmade H2O Fixed Blade Dive Knife (112SBK-BLK): A Purpose-Built Safety and Rescue Knife for the Water

The Benchmade H2O is a fixed-blade knife designed for divers, water rescue workers, and anyone who needs a reliable cutting tool in or around the water.

If you dive in conditions where entanglement is a real risk, work in water rescue, or simply want a serious, no-compromise dive knife that will not let you down when it matters, this is worth your attention.

What You Are Getting

The H2O is a fixed-blade knife, not a folder. Fixed blades deploy instantly with no mechanism to fumble, which matters when you are task-loaded underwater or your hands are cold and gloved.

The total length is 8.07 inches, putting it in the full-size working knife category rather than the compact backup category. It is designed to be your primary cutting tool, not a last-resort pocket blade.

The blade is a drop-point shape with a serrated (combo) edge. The drop point gives you a strong, controlled tip for piercing. The serrations do the real work on rope, netting, monofilament, and kelp, cutting through fibrous material faster than a plain edge in a single draw. This is the right edge geometry for entanglement emergencies.

The Steel: N680

Benchmade chose N680 stainless steel for this blade. N680 is a high-chromium steel developed specifically for wet and salt-water environments. It holds an edge well and resists corrosion far better than general-purpose stainless steels, which matters when your knife lives in a dive bag, gets rinsed imperfectly, and goes back into salt water week after week.

You still need to rinse and dry it after use. No steel is truly immune to salt. But N680 gives you meaningful real-world protection against the rust and pitting that will ruin a lesser blade over a season of diving.

Handle and Grip

The handle is textured Santoprene, a rubberized overmold material that stays grippy when wet. It is ambidextrous, so it works equally well in either hand. In practice this means you can draw and use it without thinking about orientation, which matters in a stressful situation.

Sheath and Deployment

The sheath is molded thermoplastic with a thumb-release retention system. One-handed deployment is the point: press the thumb release, the knife comes free. When you are managing a line, a buddy, or your own buoyancy at the same time, that single-hand draw is not a convenience, it is the whole design goal.

Confirm the sheath attachment method suits your BCD or harness before purchasing.

Benchmade LifeSharp

Benchmade backs the H2O with their LifeSharp service for the life of the knife. Send it in and they will re-sharpen it to factory spec, clean it, oil it, and make adjustments, at no charge. For a safety tool that depends on staying sharp, this is a meaningful commitment. A dull dive knife is nearly useless in an entanglement; knowing you can restore the edge properly, without guesswork, has real value for a knife you plan to keep long-term.

Who This Knife Is For

The H2O is well matched to recreational and professional divers who treat their cutting tool as safety equipment rather than an afterthought. It is also a logical choice for water rescue personnel, lifeguards, and military or tactical users working in aquatic environments.

At 8 inches overall it is not a compact, low-profile backup blade. If you are looking for something small to tuck discreetly onto a BCD strap as a secondary tool, this is probably larger than you need. But if you want one serious, dependable knife that covers entanglement emergencies, general underwater work, and rescue situations, the H2O is built for exactly that role.

Care is straightforward: hand wash only, and rinse thoroughly after salt water exposure.