Foam body armor? In tests conducted by the development team, the foam body armor was able to defeat an armor-piercing bullet. The strike face - the side facing the weapon - was made with the new composite metal foam together with boron carbide ceramics. In basic terms, the foam is a composite metal foam. For example, their lightweight stainless steel foam was far more effective than stainless steel.

Source: Fox News February 23, 2017 16:07 UTC