Alien fabric

The material of the Gray's jumpsuits and the Behemoth's coverall is an unknown material with an extremely high strength-to-weight ratio. It can still be incredibly tough, even while being thin. It's lack of rigidity does little to mitigate blunt force and kinetic energy, though its composition and ability to dissipate heat may provide improved resistance to some energy weapons.

This material has not yet been researched. Until such time, exact specs will remain a mystery and it cannot be reproduced.