Sub-Dermal Armor

 is a Fallout: New Vegas perk.

Effects
Increases your total Damage Threshold by 4. Permanently adds weight to your inventory. It does not, however, add weight to your armor, so it might prove usefull for players with high Sneak and/or the Travel Light perk.

There may be a glitch where the player might have to remove and re-equip the armor for the +4 damage threshold to take effect.