Application range: It is also appropriate for long-term static preservation of a large number of biological samples such as stem cell, plasma, semen, embryo, tissue, organ, and so on. Production technology: Unique patent technology of evacuation and multi-layer insulation technology ensure an extremely low loss rate of liquid nitrogen evaporation. All weld joints go through mental flaw detection and helium mass spectrometer to see if there is leak. Every product goes through strict liquid nitrogen test. Unique polishing technology ensures aesthetic modeling. The entire manufacturing process follows strictly iso9001:2008 and iso13485:1996 quality control procedures. Production materials: Materials of inner tank and outer tank are made of 304 austenite stainless steel of fine quality. Adsorbents are all regenerated and activated. Materials of multi-layer insulation are made of oil-and-lipid-free thin composite. Product feature: 1.-196 degree immersion cryopreservation and -190 degree vapor cryopreservation can alternate freely 2.Effective insulation ensures 98% of system surface is shrouded by vacuum 3.Powerful control and management system, automatic fluid infusion, real-time monitoring of liquid level, temperature and other data are installed 4.Compared with equipments of same functions, it saves 70% of liquid nitrogen and reduces maintaining costs to the lowest degree. 5.Pallet rotation in the inner tank makes access convenient.