Stonewall (Fallout: New Vegas)

Stonewall is a Fallout 2, Fallout: New Vegas, Fallout Tactics and J.E. Sawyer's Fallout Role-Playing Game Perk.

You are much less likely to be knocked down in combat.

Fallout: New Vegas
You gain +5 to your Damage Threshold against all Melee Weapons and Unarmed attacks, and you cannot be knocked down by any means in combat

Behind the scenes
The picture used is a reference The Thing, a member of the Marvel Comics superhero team The Fantastic Four.