In saltwater conditions, titanium outperforms stainless steel, offering edge retention and blade strength comparable to steel knives but with less weight and much better corrosion resistance. The 4-3/8-inch blade will need regular but ordinary maintenance, dulling at a normal rate during use, but you won't need to worry about the titanium edge rotting in the sheath. Titanium doesn't corrode even if stored in seawater.

The Promate Diving Knife was designed by scuba divers and includes special features professional divers find handy. The sharp tip and plain cutting edge handle stabbing and slicing tasks, and on the blade spine, you'll find a serrated section for tougher cable-cutting chores. The diving knife's spine also holds a deep notch for quickly severing smaller lines. A rubberized grip fully encloses the knife's tang, and bolsters keep your hand on the grip whether you're cutting with the blade or smashing and banging with the titanium hammerhead in the butt of the handle.

The Promate Titanium Diving Knife comes with an adjustable sheath made to strap securely to arm or leg. The knife snaps into place for secure carry in any position. Although designed especially for divers, the knife offers many features equally useful in survival situations on land.

See the Barracuda Sharp Tip from Promate for another good titanium knife in a larger style.

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PROMATE Snorkeling Scuba Dive DRY Snorkel PURGE Mask Gear Set Titanium US $42.98   Auction Ends: 28d 16h 57m

Promate Sharp Tip Titanium Scuba Dive Snorkeling Backup BC Knife 3 Blade US $49.95   Auction Ends: 6d 59m

The Model A500 Offshore Knife has now become standard equipment for Coast Guardsmen, Merchant Marines, and anyone who works with heavy rigging. When you need the quickest answer, the Model A500 provides it. Only eight inches long and seven ounces in weight, the concave cutting edge is designed for cutting rope and harness fast. Machined and ground from a single bar of heavy 440C high carbon stainless steel, the A500 shows good corrosion resistance and holds a cutting edge well. Since users who spend long periods on the ocean can't get by with serrated blades that only get sharpened at the factory, Myerchin designed a serrated edge which can be resharpened by hand with a tapered round file. In the corrosive conditions of extended time at sea, some careful maintenance keeps the A500 in top shape.

The flat build of the Myerchin A500 -- combined with the versatile mounting options of its sheath -- allow sailors, fishermen, and climbers to lash the knife to gear or wear it on the belt. The low profile of the system reduces its chances of snagging on other equipment or catching on natural obstacles. The nylon fabric sheath includes a Velcro-closure flap that keeps the A500 in place in any position. String a wrist loop through the lanyard hole in the tang for extra security.

If you've been waiting for a serrated knife you can actually keep sharp, the wait's over.

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Myerchin Knife Offshore Safety Dive Knife and Marlinspike Spike with Sheath A508 US $79.95   Auction Ends: 24d 21h 41m

Myerchin Knife Offshore Safety Dive Knife with Sheath A500 US $54.95   Auction Ends: 24d 21h 17m

The Fusilier is an upgrade of the UK Sabre, another blunt-tip knife/tool made of less rugged materials than the Fusilier. The four-inch-long, double-edged blade of the Fusilier has a more efficient serrated side than the Sabre, and this prybar-style knife is made from UK's own alloy, Hydralloy. Hydralloy was developed to provide better durability and corrosion resistance than the 440C of the UK Sabre but remains lower priced than UK's best titanium knives.

Although many would certainly prefer a strong knife point rather than the blunt chisel of the Fusilier, if your work or hobby requires frequent use of a chipping or prying tool, the Fusilier certainly provides that. The strong handle includes a deep finger choil for a solid grip on the tool and does have enough width for twisting power. Most functions of a knife blade are still covered by the Fusilier, which also has a cord-cutting notch ground into the base of the knife's plain edge. The Fusilier has some handy potentials, but it might make a better accessory than a primary dive knife. Points still come in handy for most of us.

The friction locking sheath of the Fusilier could be worn on gear belts or straps, or bolted to equipment through the sheath's pre-bored mounting holes, and holds the tool securely in any position.

If you'd like a larger dive knife that's a cutter, check out the UK Titanium Dive Knife with spear-point blade.

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Underwater Kinetics DIVE KNIFE FUSILIER UK30231 US $55.00   Auction Ends: 22d 21h 2m

Underwater Kinetics UK Fusilier Compact Dive Knife Ye US $41.08   Auction Ends: 16d 23h 47m

The four-ounce knife of AUS8 high carbon stainless steel incorporates a modified tanto point for efficient penetration. Construction is extremely simple, with easily gripped Kytel handle slabs that provide nonslip traction in all weather conditions. Hardened to HRC 56 to 58, the 8-1/4-inch knife takes a razor edge and holds up to heavy cutting. To increase corrosion resistance, the steel is first polished to a mirror finish, sealing the pores of the metal, and then coated with dark titanium nitrate for a long lasting barrier against chemicals and saltwater.

The Operator's Model A.B.C. offers full sized capability in a small package suitable for hikers, backpackers and fishermen as well as emergency rescue and tactical users. The thin handle's deep finger choils compensate well for the lack of bulk in the grip, with deep traction grooves to add even more slip-free friction. The Operator's 3-3/4-inch dagger blade fits snugly into a versatile multi-position Zytel sheath. The sheath adjusts to eight different positions and attaches to harness webbing, pack straps, Personal Flotation Devices, belts, and nearly anywhere else a user might consider it handy. Brass tension screws on the scabbard adjust the fit of the blade so it can even be carried inverted -- strapped to the leg or hung from a neck cord.

Do-everything knives usually do nothing very well, but Hammond's tactical design experience closed that gap. The Operator's Model A.B.C. actually works.

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The handle is an open tang design, to reduce weight, and injection molded with plastic and co-polymers. The neon accents serve more than just a style purpose: the bright colors are intended to increase visibility in the dim and murky environment of the marine world. Accidentally drop this knife on a shallow dive and it will be easier to spot and recover. A stainless steel tank signal is located on the butt.

The overall length of this blunt tip Sea Hunter is 7 5/8-inch. The included quick-release sheath, like the Kershaw Amphibian, comes with leg straps. With the sheath's clip system, however, the Sea Hunter (in sheath) can be worn in a variety of alternative ways: on the BCD, netting, or webbing. Overall, not a bad knife to go diving with.

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Kershaw Sea Hunter Knife Blunt Tip Model 1008BL P NEW US $28.95   Auction Ends: 23d 3h 22m

At only 7 3/4-inch total length and weighing in at 3.2 ounces, stored in its lightweight Kydex sheath, this small addition will make up for all the other gear you have to carry. The blade is a 3.75-inch 420J2 stainless steel, spear point, double edged - one plain edge and one tidy serrated edge. The handle is a 420J2 stainless steel skeleton with co-polymer insert. The blade can get razor sharp and the steel frame handle equals strength and stability, while the co-polymers insert saves a lot of weight. Not likely you'll need it, but the Amphibian comes with a limited lifetime warranty.

I, personally, would carry this knife diving. The serrations are good for lines and ropes. The stainless steel skeleton handle makes a fine tank signal. The sheath is lightweight, attaches to the leg where I like it, and works smoothly. Those are my necessities. But, for the safety conscious, Kershaw also has the blunt tip Sea Hunter, which is more in the traditional design of a dive knife.

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KERSHAW DEAL OF THE DECADE 1006 AMPHIBIAN BOOT KNIFE MADE IN JAPAN US $53.99   Auction Ends: 5d 2h 13m

KERSHAW AMPHIBIAN 7 3 4 420 stainless SERRATED KNIFE KS1006K US $45.00   Auction Ends: 19d 18h 22m

First the good feelings: I think the orange nylon handle is attractive, decently sized (4.1-inches), and easy to grip. It is also available in black, which looks good with any diver's gear. The orange, though, makes for easy spotting in the murky depths. Also, I think the 3.2-inch blade is a modest-quality stainless steel in a design that works great for casual submerged use: blunt tip and partially serrated. Blunt tip is a responsible choice of knife to carry while diving - in underwater conditions, it's hard to look out for your surroundings, and often certain gear, like gloves, can hinder your normal mobility and carefulness. That's a bad combo when carrying a knife with a clip, drop, or spear point. Sure, a sharp point means you can show that shark who's boss if need be, but that's an unlikely scenario. More likely than not, a dive knife would be like a safety pin against serious sharks. And the function of a dive knife is not to protect against underwater life - it's to use in an emergency to cut yourself free from lines or other dangerous situations. That's where the partially serrated edge is very handy to have. I always buy a dive knife with a serrated option.

Here the bad feelings: This knife doesn't have a tank signal option, a specific line cutter option, and the sheath isn't my favorite thing ever. Tank signal is important for underwater communication. Banging the butt off your knife against the tank is the best method I've found. A line cutter specifically for cutting lines isn't that big of a deal, but I like it. And a sheath is important because fumbling to get a knife out at a hundred feet underwater could be the last thing you ever do. And other than those three things, I still have some other beef.

This knife reminds me of the blunt tip Gerber River Shorty, in that they are nearly identical designs, but the folks at Gerber usually market the River Shorty as intended for rafting and paddling sports. If you wanted, it could be a dive knife, but calling it a dive knife outright is a bit far-fetched. Any serious diver knows that top-notch equipment is going to be the difference between life and death. That's why I always have a hard time making dive knife recommendations - what I consider important might not matter so much to another diver. They might seriously need that sharp point to kill sharks. They might like the Schrade Water Rat's simplicity. Before you decide, at least check out the U.S. Divers Titanium 5-inch Dive Knife, which I've recommended as a great alternative choice in most of the dive knife reviews I've done. The titanium blade won't be a sharp, but it will last longer in wet conditions. Or, the Gerber River Shorty is a good alternative stainless steel blade at, last I looked, at a cheaper price.

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SCHRADE SHRADE BLACK WATER RAT RIVER RESCUE KAYAK DIVE KNIFE SCHWR1 US $26.00   Auction Ends: 27d 4h 34m

SCHRADE KNIVES WRO ORANGE WATER RAT TOOL 7 3 8 FIXED BLADE KNIFE NEW SALE PRICE US $18.49   Auction Ends: 26d 21h 24m

This Alligator Sharp Tip clip point, plain edge blade is constructed from 301 stainless steel, a mildly appealing metal for a dive knife, and comes with serrated spine and line cutter. The black handle completely disassembles for cleaning and maintenance. A hard plastic sheath with adjustable leg/ankle straps is part of the purchase.

So, do I recommend the Alligator Sharp Tip? It is a decent quality for a good price. But looking at the design, I can't help but think of the U.S. Divers Titanium Dive Knife. Again, made by a company which specializes in diving, not knives, but this is a much higher caliber knife which also disassembles and will last much longer.

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Alligator Blunt Tip Stainless Steel Scuba Dive Knife US $29.95   Auction Ends: 18d 2h 44m

KF690 Alligator Sharp Tip Titanium Dive 55 Knife new US $66.95   Auction Ends: 24d 21h 20m

The great thing about this knife is that it is easy to keep clean. The simplicity of the design means that getting salt and grime off the surface is no problem. I would say, for the serious diver, definitely look elsewhere. But if you only get to diving a few times a year, and don't find much need for your knife, then this would be a fine choice.

If you're looking for something a bit more high-end, check out our complete selection of dive knife reviews.

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The blunt tip of the Sabre is designed for safety, and will be good for prying if need be, but there are many advantages to a spear or clip point design. This is almost a double-edge blade, with one straight-edge and one serrated. There is line cutter near the base on the serrated side. Like most dive knives, there is a metal tank signal piece on the butt of the knife. The sheath attaches to the leg and utilizes a quick-release mechanism.

In my opinion, this dive knife might be a good buy for the casual or beginning diver who don't get much use out of their dive knife. But for the serious underwater explorers, diving a wreck or somewhere with a good chance of some loose tangles of line, I probably wouldn't want to be caught with this knife.

I like U.S. Divers, so I might go with the U.S. Divers 5-inch titanium blade. Or, in blunt tip, the Underwater Kinetics Blue Tang titanium blade is a good quality. Titanium blades just last longer than to stainless steel.

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