PolarSafe cryo/freezer boxes and dividers are made of sturdy white cardboard, with a moisture-repellent coating to protect form the effects of liquid nitrogen or condensation from refrigerated equipment. Boxes are sized to fit all standard stainless-steel and polycarbonate storage systems. Small holes on the bottom allow for safe drainage of liquid nitrogen or water. For use in mechanical freezers and liquid nitrogen tanks at temperature to -196°C.