The Eppendorf CryoCube F570 series of ULT freezers (also known as ultra-low temperature freezer/-80 °C freezer) is based on a strong compressor for fast recovery to -80 °C after opening. As this class of freezer is often used as real-lab freezer, multiple openings per day are normal – a dynamic and strong cooling system is mandatory for fast recovery to -80 °C after every opening.