Blue. FreezeBox™ is a new, energy-saving, environmentally friendly and safe cooling equipment, without additives. It does not require electricity (except for pre-cooling the cores in the freezer) and no ice for low-temperature cooling of biological samples. The system can be used ice-free, is lightweight, easy to transport and ideal for the collection and storage of biological samples. It can be combined with interchangeable cores and different tube modules. Cooling cores can be tempered in a refrigerator or freezer and inserted into the FreezeBox™. For operation with dry ice, leave out the cooling core and fill with 200 g dry ice instead.