Well, the Plano Sportsmans Trunk(medium) has been in the back of my Forester, up top, filled with catfood,rice, and whatever else I had laying around. I sat on it, used it as a small table, sprayed it with a hose rightside up, and upsidedown. It sat out in the rain last night(on the ground). No water, dust, dirt, debris entered into the box. While using it as furniture, there was no flex, no crackling, no evidence of stress. The sweet upside, is that they are made to stack, and mostly lock into place. I can fit a total of six in the trunk of my car, or ten with the seats down.