working Principle: After the air is filtered through the high-efficient filter,the fresh air comes into feeding area for SPF rabbits. .. There is a stainless steel rabbit cage rack(2 layer*3 cages) in the feeding area.The wast gas release by he animals,after filtration of coarse filter and high-efficient filter,is exhausted to the outdoor environment.For negative-pressure type equipment,there is blower fan behind the high-effcient filter of air outlet.The blower fan sucks air from the Isolator to create a negative pressure in the feeding area,so as to prevent leakage of harmful microorganisms from experiment processes.