The snap-tight Cambro 1218CP148 Poly 1/2 Size Flat Food Box Lid won't come off during transportation. Features top molded-in rails for safer and more secure stacking. Lid is made of impact, stain and chemical resistant solid white and withstands temperatures from -40°F to 160°F (-40°C to 70°C). Measures at 18 inches long by 12 inches wide.