Wound packing, besides applying a tourniquet, is one of the most basic techniques of bleeding control in a pre-hospital environment. In theory, the concept is relatively simple: hold pressure on a wound, and after several minutes, the applied pressure will help to encourage the body’s natural clotting factors. This can vary from just three minutes of pressure if using specially manufactured gauze (i.e. Combat Gauze) impregnated with hemostatic agents, to 10 minutes if using standard gauze or other fabrics.


The trick to this technique, however, is that the correct pressure application point may be several inches down inside the muscle. Pressure is much more effectively generated once you reach a hard surface, such as a bone, to push against. Otherwise, trying to compress relatively squishy fat and muscle starts to feel like pushing rope.

The Wound Cube from Phokus Research Group is a new training tool to help teach this vital technique. We’re featuring it because it’s difficult to make a similar tool on your own, and even harder to make it for less money than its current retail price.

Misleading Instincts

A layperson’s instinctual reaction when presented with a heavily bleeding wound is often to apply pressure directly on top of the skin, possibly with their hands. Even if they have gauze, their first reaction is often to try and mash a ball of it into the wound from the top. A more appropriate technique, however, is to feed gauze or other wound-packing material starting down at the bottom of the wound, slowly packing from the bottom until the wound is filled. At that point direct pressure will be applied from the outside surface (skin) and this pressure becomes directly transmitted to the base of the wound — exactly where we want it.


Above: Using a flashlight to illuminate the inside of the Wound Cube allows for instant feedback as to whether or not your wound packing technique is properly filling the wound cavity.  

Take a standard gunshot wound as a classic example. Those familiar with ballistic impact response may already know that a wound into flesh can create a narrow channel at the start, gradually expanding into a larger wound cavity as the bullet expands or mushrooms. It would be impossible to apply adequate pressure on the inside of the expanded chamber by pushing from the outside.

But by feeding gauze in with your fingers, ½ inch by ½ inch, the wound cavity can be filled correctly. This isn’t easy. Because gauze is flexible and non-rigid, it can be tough to feed it down a narrow tube where you can’t see what you’re doing or where it’s going. It’s an acquired technique and, like many survival skills, requires periodic refresher training.

Feels Like Warm Apple Pie


Enter the Wound Cube. The cube, designed to accurately depict the texture and feel of a traumatic injury in flesh, features several types of correctly modeled and sized wounds. These include lacerations as well as different types of gunshot wounds. The ballistic patterns are authentic, recreating the narrow entrance channels and larger interior cavities created by a gunshot wound. Its durable silicone also features realistic tissue density and is textured to feel similar to human skin, especially when a few drops of simulated-blood lubricant is added.

For those of you who may be familiar, yes, the Wound Cube is based on the same materials technology as the Fleshlight. The versatility of science can enrich many facets of our lives.

How It’s Used


A Treasure Island (FL) police officer honing her wound packing skills using the Wound Cube silicone block.

The mechanics of using the cube are simple. Basically, it’s an inert block of silicone with holes that you stick your fingers (and only your fingers) into. Continually training on the act of feeding gauze into the tiny holes with your fingers will make it that much easier if you ever have to aid a victim who’s been shot or stabbed — at least if that injury is to the arms, shoulders, or legs. Wounds in places like the chest, abdomen, neck, and head often require advanced care techniques, and it’s usually better to focus on rapid evacuation, as covered in Issue 5 of our sister publication CONCEALMENT.

The Wound Cube is made from clear silicone, making it semi-transparent and easy to confirm that you’re effectively getting the wound-packing material to the base of the wound inside the body. While you’re getting to third base with the cube, an instructor can shine a flashlight into one of the other open holes to illuminate the inside of the channels and make easy visual confirmation on how effectively you’re packing the wound.

Practicality and Effectiveness

Although the premise of the Wound Cube is very simple, it’s also very effective and robust. Wound packing isn’t a delicate act — fingers have to work fast, plunging repeatedly into the wound cavity in an effort to tamp down as much gauze as will fit inside, in a hurry. First timers or the untrained may look like they’re delicately trying to knead the world’s tiniest pizza dough, softly feeding one finger in after another and alternating index fingers. More experienced medics on the other hand, may use more arm motion to aggressively pack in the gauze and make sure they’re hitting the bottom of the wound or a hard bone.


The point is that if these cubes are being regularly trained on like they should, the relatively small wound channels will see a lot of action from big fingers, which raised a question in our minds about whether the holes would inadvertently split or expand. Phokus Research Group states that they’ll stand behind their product and offer a five-year guarantee that the wound channels won’t “stretch out” or increase in size from regular use.

Unfortunately, we didn’t have five years to test this thing, but we did have one night of intense training in a bleeding control class taught by our friend Detective Eric Soderlund, who is featured in RECOIL OFFGRID Issue #25 teaching improvised evacuation techniques. Along with law enforcement officials from the Treasure Island, Florida Police Department, we went family style on the Wound Cube and passed it around the class.

The difference was immediately obvious. Unlike the other homemade training devices which Eric had painstakingly carved out of foam blocks, the cops using the Wound Cube had instant feedback on not just the mechanics of their wound packing techniques, but visual confirmation once the gauze had completely filled the hole. This made it easier for the students to adjust their techniques since their performance was so easy to measure.

The only component that didn’t make sense to us was the simulated laceration wound. We thought the laceration was too shallow and didn’t allow a lot of gauze to be packed into the wound. We took an X-Acto knife and cut it a bit deeper, but that was only marginally successful.

Final Analysis

With a price point starting at $140 and first responder discounts available, the Wound Cube is a relatively affordable, durable training tool that’s significantly less expensive than similar competing products. For a homegrown alternative, there’s no easy way to accurately recreate the enlargement of the wound cavities as they vary in depth, and it becomes even more difficult if you’re trying to find a semi-transparent material so you can actually see what’s happening inside.

Similar to the idea that it’s better to have a small-capacity, small-caliber handgun on your person than a larger “better” weapon in your truck, we feel it’s preferable to have a tool that aids in realistic training for bleeding control, instead of thinking you can improvise or figure it out on the fly. It’s not perfect, but it fills a very specific niche that has never previously been addressed at this price point and with such ease of use. Overall, we like what we’ve seen and what we felt when we were inside the Wound Cube, and we’d definitely take it home to meet our parents.


Wound Cube

4 x 4 x 4 inches

2.5 pounds



About the Author

Andrew Schrader recently served as an advisor/reviewer for the San Bernardino (CA) City Fire Department’s After Action Report (AAR) of the Active Shooter Incident Response which took place in December 2015. His company, Recon Response Engineering LLC, educates firefighters and search-and-rescue teams on the subject of urban search-and-rescue and building collapse. Most recently, he was deployed in Florida to support rescue operations following Hurricane Irma. www.reconresponse.com / @reconresponse

STAY SAFE: Download a Free copy of the OFFGRID Outbreak Issue

In issue 12, Offgrid Magazine took a hard look at what you should be aware of in the event of a viral outbreak. We're now offering a free digital copy of the OffGrid Outbreak issue when you subscribe to the OffGrid email newsletter. Sign up and get your free digital copy

No Comments