-85?, 405 liters, Chest type Deep Freezer 1. Deep freezer for preserving items to be stored without changing of physical and chemical characteristics in ultra low temperature of -85?. Freezer has realized the ultra low temperature by using environment friendly complex refrigerant and non-CFC high density polyurethane insulation, and is equipped with the heat exchange system of optimum design, one touch screen panel of operating convenient, sophisticate temperature controls and monitoring system controlled by a microprocessor, safety and alarm system for preparing sudden power fail and a state of emergency over the freezer operating. 2. Temperature Control System In case of changing the set temperature of freezer, the determined changeable set temperature value, which is changed according to the ambient temperature, shall be set. The set temperature is changed automatically if the current ambient temperature rises higher than the time of setting temperature, but in case of going down, the set temperature keeps the first set value. If the chamber temperature deviates from the set range, it sounds an audible warning.