The core feature of liquid armor is a shear thickening fluid composed of hard particles suspended in a liquid. The liquid, polyethylene glycol, is nontoxic and can withstand a wide range of temperatures. Hard, nanoparticles of silica constitute the other component of the liquid. The liquid stiffens instantly into a shield when hit hard by an object. It reverts to its liquid state just as rapidly when the energy from the projectile dissipates. Testing has shown that the liquid works best when integrated into the DuPont Kevlar. By holding the fibers of the vest tight, the liquid disperses the impact of a blow better than fibers alone, allowing the energy to be spread over a larger area. The liquid can be applied to conventional ballistic fabrics or other materials used in armor application. The treated material remains flexible under normal wear, but becomes instantly resistant to penetration when impacted by a spike, knife, or high-velocity projectile or fragment. Extensive testing has shown that conventional ballistic fabrics treated with the liquid can resist penetration by an ice pick that would otherwise easily penetrate the fabric. Because liquid armor enhances the functioning of materials such as Kevlar, it may be possible to reduce the number of fabric layers required to defeat ballistic and stab threats, such that vests could be lighter and cheaper.