Ultra-low temperature (ULT) freezers are designed to provide laboratories with an energy-efficient approach to cold storage. The freezer line incorporates a choice of high-performance or energy saving modes, which are easily selected by the user via the intuitive touch-screen interface. Providing sample protection while using significantly less energy than previous-generation Revco models, the new range of freezers helps laboratories to obtain an energy-efficient approach to maintaining sample viability during long- and short-term cold storage. The freezers also offer temperature uniformity throughout the internal chamber. As a result, users can maximize the use of all available space with the knowledge that all samples will be held at the pre-set optimal temperature.