Sniper (Fallout: New Vegas)

Sniper is a perk

Effects
With the Sniper perk, the chance to hit an opponent's head in V.A.T.S. is increased by 25%. This bonus is multiplicative, not additive, as is true for most perks that increase the chance to hit in V.A.T.S. This means that, for example, a 50% chance to hit an enemy's head without the perk would have a 62.5% chance with the perk (50% * 1.25 = 62.5%).