Kilograms or Pounds What's the Big Deal

Brian wanted to make sure we weren't over on the luggage weight. He brought a scale downstairs and weighed the bag. To my total amazement it was only half full but at the weight limit. I confirmed the limit. Frustrated, we closed the bag and tried to shove everything else in the carry on bags. We get to the airport and put it in the scale. Half the allotted weight. Brian's face sunk. "I weighed on pounds not kilograms. Sorry. Hey! We can get lots of souvenirs now!!"