The small quantity of powders placed in envelopes makes it difficult or impossible for other technologies to detect. With the live 3D video provided by MailSecur, an operator can physically move the envelope and see the actual grains of powder moving within the mail item.
With liquids, in the same manner as powders, while an X-ray scan may pick up the outline of the substance, it cannot discern the movement. Yet, the MailSecur operator can manipulate the items and easily determine a liquid substance even much smaller quantities than can be detected by X-ray.