According to the Air Force Times, Air Force Academy Cadet Hayley Weir has created a unique gooey substance that can stop a bullet.

Her creation was the result of a chemistry class project, in which her professor gave the students epoxy, Kevlar and carbon fiber – materials that would harden together to stop a bullet but that could also shatter. To combat this issue, Weir had to come up with an alternative combination of materials that would produce the same result without shattering. She used a special thickening fluid as an alternative to the epoxy. The goo-like fluid changes viscosity depending on whether stress or force is applied to it.

As Air Force Times explains, this means the material would feel gooey until struck with something, like a bullet — then it would harden enough to stop it. The concept of separately using shear thickening fluid, Kevlar and carbon fibers as anti-ballistic materials is not new, but they’ve never been used together.

Weir began researching in 2015 and began testing in early 2016. In the beginning, Weir says, the goo wasn’t working as intended. Weir and her test partner Ryan Burke determined the materials needed be layered differently, and by December 2016, they had their first successful test.

The team tested 9 mm, .40 Smith & Wesson and .44 Magnum rounds. The stronger and faster the round, the quicker it was stopped by the material. In the 9 mm testing, the rounds went through most of the layers but were caught by the carbon fiber backing. The larger .40-caliber round was contained in the third layer of Kevlar. The .44 Magnum was caught in the first layer.

Weir says they’re looking at the possibilities of using the material as extremity armor as well as coating vehicles and aircraft in it. But the possibilities don’t end there. The goo could also be applied to tents and emergency barricades. The material is currently patent pending and will remain so for a year.