3 guys walk into a bar

The first guy says "I got the smallest arm in the world"

The second guy "I have the smallest head in the world"

The third guy "I have got the smallest dick in the world"

The 3 guys go to the Guinness World Records

The first guy comes back and says "I really do have the smallest arm in the world"

The second guy comes back and says "Amazing, I do have the smallest head in the world"

The third guy comes back angry "Who the F**K is JUSTIN BEIBER?!"