A mains electricity (AC-powered) laboratory appliance designed for extended cell/tissue (e.g., ovum, embryo, bone, cornea) storage, at temperatures below the point where most all biological activity ceases, using liquid nitrogen (LN2) as the cooling agent and vapour-stage nitrogen for storage [storage temperature of -140? Celsius (-220? Fahrenheit)]. The device typically consists of a chamber with two vessels separated by a vacuum space; automatic temperature controls; an external container to replenish the cryogenic fluid; a pressure-relief device, alarm, recorder; and a pressure-control valve. Cells/tissues are immersed in the vapour atmosphere above the LN2 in appropriate containers.