The SICH system also has a standard and/or custom-made Passbox range that allows the exchange of material between classified or unclassified rooms, without interfering with the pressures or temperatures of the rooms, in controlled environments, without compromising the sterility of the material or the clean room. It is designed for laboratories, hospitals, biological environments, and clean rooms in general, complying with GMP and FDA regulations.

They have two interconnected doors with a double electromechanical interlocking system, so that both doors cannot be opened simultaneously. The equipment works as a locking device, preventing the contaminated environment from passing to the other clean room.