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A revolutionary new armor relies on a liquid that hardens when something hits it, promising unprecedented protection while letting soldiers move freely, unrestricted by bulk and weight.

Protection for warriors has long meant weight and bulk from ceramic plates and Kevlar that cover large areas of the body but reduce maneuverability, agility and speed. And in war zones like Iraq and Afghanistan, temperatures can reach 120 degrees Fahrenheit, meaning heavy armor can also accelerate fatigue.

The new super gel from global defense, aerospace, and security company BAE Systems means body armor that will provide far greater protection at a drastically lighter weight -- with more flexibility to boot.

The liquid can even be pasted between sheets of Kevlar, the body armor standard considered five times stronger than steel -- and transforming it into super armor thinner and about half the weight of the average bullet-proof vest.

Formally known as Shear Thickening Liquid, the fluid has special particles that are freely suspended. The particles collide when the fluid is disturbed, which creates a resistance to the disturbance.

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When the force of the disturbance is large enough, the particles will then actually “lock” together. So when a bullet hits the material at speed, the liquid armor absorbs the impact energy and hardens extremely quickly.

Imagine slowly stirring a container of Shear Thickening Liquid: You would feel little resistance initially, and the faster you stir the more the resistance would increase, explained Stewart Penney, head of business development for design and materials at BAE.

The special liquid can also be incorporated into conventional Kevlar body armor; when put together the liquid and Kevlar provide excellent freedom of motion and armor 45 percent thinner than existing types.

The liquid goo would also restrict the movement of the Kevlar fabric’s yarn, expanding that the area over which impact energy is dispersed.

When a bullet strikes, conventional body armor tends to bend inward, preventing death but often leaving considerable damage and pain. This wide dispersal of energy could prevent painful bruising, cracked or broken ribs and even trauma to internal organs that accompany being shot in the armor.

A video shows researchers at BAE Systems’ Advanced Technology Center testing the material by firing bullets from a 9mm handgun into 10 layers of Kevlar combined with the liquid armor and then 31 layers of untreated Kevlar.

It shows the liquid armor being struck by a bullet, and the impact dispersing over a wide area -- meaning the chances of a fighter being injured or killed by the force of a bullet is reduced because it is not concentrated on one small area.

With standard ceramic plates, a flak jacket can weigh approximately 25 pounds. BAE Systems is confident that the liquid armor could weigh half as much -- meaning greatly reducing burden for warfighters, allowing them to do their jobs more effectively.

Next steps for liquid armor could include developing it so that it can withstand the force of more powerful weapons such the AK47.

Beyond the military, there is great potential for developing a version that could be very useful for first responders like police forces and ambulance crews.

Cutting-edge body armor can reduce the risks for the warfighter and first responder whose work can be very dangerous, and could go a long way to keeping them safe while allowing them the freedom of movement to do their job.

Ballet dancer turned defense specialist Allison Barrie has travelled around the world covering the military, terrorism, weapons advancements and life on the front line. You can reach her at wargames@foxnews.com or follow her on Twitter @Allison_Barrie