July 19, 2007: A British firm (BAE) asked why the Slat armor (most prominently used by Stryker armor vehicles since 2003) had to be made of steel. So BAE fabricated a set of slat armor made from aluminum, and tested it. Worked just as well as the steel version, and weighed over a ton less.

Slat armor is a 2.5 ton cage of armor that circles the vehicle. It is similar to anti-torpedo nets that used to protect battleships in port. When an RPG hits, it is detonates between the main armor and the metal slats, and does little harm. Slat armor costs about half as much as ERA (Explosive Reactive Armor), and is about a third lighter, but it is unwieldy. However, in practice, slat armor works quite well, and many other types of armored vehicles, particularly armored trucks, use it as well.