The straight razor is an old-fashioned shaving razor with a polished wooden handle. Though its blade is short, it's lightweight and can deliver several slashing hits in rapid succession. At the cost of 15 AP, you can perform a V.A.T.S. attack called Back Slash, which does 70% damage. It also provides bonus Critical chance and bonus Critical damage.
This weapon is classified as a "Holdout" weapon, and can be smuggled into areas that prohibit any kind of weapons. It's the second weakest weapon, only "outdone" by the rolling pin.
Figaro, a silver straight razor that is more damaging and has an even faster rate of attack.