603556 series of safety controlling cabinet is developed with the theory of simple bio-safety cabinet, the input and output of wind are strictly filtered with high-efficiency air filter, which can ensure the negative pressure and cleaning in the chamber, the theory of 603556 series is same with that of B2 safety cabinet, but it is no so much stricted on the concept of biology safety controlling, it is suitable for the lab sample and studying job which has small effect for the circustance and the operator.