The WASP Injection Knife

A few weeks ago I got a call from a friend and neighbor, Sandy Rondinone, telling us to watch "Law & Order" that night. I don't normally watch that show, but I knew why she wanted us to see it so I put it on. Sure enough, in the last ten minutes, Det. Fin Tutuola and Det. Elliot Stabler come upon the evil businessman (the bad guy's always an evil businessman), now dead with his abdomen blown open.

Fin says, “Just when you think you’ve seen everything.”

Stabler adds, “It looks like he ate a bomb.”

Soon, Stabler identifies the weapon: "It was a WASP injection knife, developed for the Navy Seals for the special punch it packs. Inside the handle is a canister which injects CO2 into whatever you are stabbing, and it blows them to bits."

The show discussed the knife's capabilities at length--it was like a five minute promotional film.

Patent drawing of the WASP Injection Knife

The reason my neighbor told me to watch the show was that her husband, Greg, is the inventor of the WASP injection knife. I remember talking to him about the idea five or six years ago. A serious diver, he developed it as a defensive weapon against sharks. He acknowledges that sharks are an overrated threat, but at the same time points out that fear of them undermines the novice diver's confidence, and restoring that confidence justifies carrying an effective anti-shark weapon. And you never know, you might actually need to use it.

 The prototype WASP knife hand built by Greg. He turned down an offer of $2,500 for it. (Click on photo for more detail.)

Greg holds the production WASP in his right hand and the prototype in his left.

A somewhat similar weapon was marketed in the 1970s, the Farallon Shark Dart. Looking like a high-tech icepick, it was more little more than a 25-gram CO2 cartridge topped with a heavy-duty hollow needle. When you stabbed the shark, the backward force punctured the CO2 cartridge, sending a ball of gas into the shark. Here is a description of the Farallon's effect: "Carbon dioxide was rushed under pressure into the body cavity. This inflated it like an automobile inner tube, making it extremely buoyant. It rose to the surface, where it died almost instantly."

The Farallon Shark Dart, from the Scuba Museum

The WASP injection knife is more versatile. It is designed first and foremost as a knife, useful for all the routine chores to which a diving knife might be put. Once its cartridge is armed, a strong blast of CO2 can be delivered through the tip with the touch of a button. The advantage of this over the Farallon is that the diver controls the release of the gas, so it's less likely to be discharged accidentally. Moreover, the cartridge holds enough for three effective bursts.

Greg personally hand-fits and test fires each knife before shipping it.

Greg told me he came up with the idea decades ago when he was running a dive shop and was hired to clear the snapping turtles out of a lake. After trying a few other approaches unsuccessfully, he settled on a lance which would inject them with compressed gas. This did the trick. Greg is a skilled tool-and-die maker and used his talents to design and build a working prototype, which has been in production for several years. So far, no reports of its use on sharks, but Greg got a report from a Western rancher who said he used his WASP knife to kill a cougar that attacked his horse (unfortunately no video on that).

The WASP Injection Knife has been featured in magazines such as Tactical Knife, Knives Illustrated, Blade, SWAT, and Soldier of Fortune. It has also been used on some of TV's top crime shows. After it appeared on the CSI/SVU episode titled "Bang," Greg got several dozen orders. Here is his website.


This YouTube video demonstrates the capability of the WASP injection knife. Greg handles the watermelons while his son G.T. demolishes them. The video has been viewed more than two million times.

Not surprisingly, the WASP Injection Knife stirred panic in the hearts of the British, that nation which, having virtually banned firearms, is now in the grip of knife-phobia. The following article appeared in the Daily Mail on July 17, 2008:

Britain On Alert for Deadly New Knife With Exploding Tip That Freezes Victims' Organs
Senior police officers have been warned to look out for a new knife which can inject a ball of compressed gas into its victim that instantly freezes internal organs. The 'wasp knife', which can deliver a ball of compressed gas capable of killing its victim at the press of a button, may be heading for Britain, the Metropolitan Police fear.

A needle in the tip of the blade shoots out the frozen ball of gas which instantly balloons to the size of a basketball, freezing organs. The Metropolitan Police have told colleagues in the West Midlands to be on the lookout for the blade, which is designed to kill sharks and bears. Police are concerned that the £200 weapon could fall into the wrong hands.

The American-made weapon is sold to hunters and divers and injects the frozen gas when the small handle-mounted trigger is pressed. The manufacturer describes it as perfect for downed pilots, soldiers and security guards and boasts that it will "drop many of the world's largest land predators".

It can snap-freeze all tissue and organs in the area surrounding the blast.

A source close to West Midlands Police said: "The Met is obviously concerned about this and that is why they have circulated the information. This knife will almost certainly kill and the Met must have intelligence that they are in circulation. I think it is only a matter of time before one of these is used because the internet makes it much easier to find and buy weapons like this."

"There should be high-profile operations and high-profile arrests against anybody caught with them. The way to tackle the wider issue of knife crime is with effective community policing, which the West Midlands force does very well."

So far, no reports that the WASP knife has invaded the British Isles. The simple fact is that most cuttings and stabbings are committed with junk: steak knives, bread knives, box cutters, ice picks and screw drivers. The number of crimes committed with expensive, high quality knives is infinitesimal.