A woman wants to find a husband so she puts out an ad "I'm looking for a man that won't hit me, won't run away, and can satisfy me."

A week later she hears a very loud knock at the door. She answers it and it is a man with no arms or legs, he says "I won't beat you, I have no arms. I won't run away, I have no legs."

She replies "And how do you know you can satisfy me?"

He grins and says "Did you hear me knocking?"