according to a survey among 150 rapist....if you're a girl...a key on hand or umbrella isnt going to dissuade them from raping u..or ur beloved one.

keys are known as short range/melee weapon....meaning in order to hit them, they are able to grab hold of u....and in a man vs woman situation, unless the chick got 6 pack and the bicep the size of my thigh, chances are the girl will be subdue....

the best weapon is probably to know the weak point of a human anatomy and a calm mind..... apart from that, GoooT Lark!