Zetix blastproof fabric resists multiple car bombs

With a bungee example:

However, if you coil a line around the bungee cord, something that defies logic will happen: the whole structure will get wider as it stretches. As you can see in the image, the line around the bungee cord becomes taut, making the bungee itself flex outward. This principle is called helical-auxetics. When you put two of these threads together, you have what Reed Richards would call an auxetic structure.