This reminds me of the following joke: A sales representative is advertising his company's invention, a shaving machine. "You put your head in a box", he says,

This reminds me of the following joke: A sales representative is advertising his company's invention, a shaving machine. "You put your head in a box", he says, "and two razor sharp knives swoosh down and cut your beard." "Don't people have different head shapes?", an audience member interjects. "Only for the first time."