Pass Box is a kind of auxiliary equipment for the clean room, which is mainly used for the transfer of small items between the clean area and the clean area, and between the clean area and the non-clean area, so as to reduce the number of times the clean room is opened and pollute the clean room. To a minimum. The transmission window is made of stainless steel plate, smooth and smooth. The two doors are interlocked to effectively prevent cross-contamination. Electronic or mechanical interlocking devices are provided and ultraviolet germicidal lamps are provided.