In normal clinical practice, when there is one specimen per container, the value of the specimen identifier and the value of the container identifier will be the same. In Figure NN.4-1, each slide is prepared from a single tissue sample from a single block (cassette). The specimen and container type for the slide are present in the Section C.7.6.22 “Specimen Module” in PS3.3 , and not repeated in the Specimen Preparation Sequence Item for staining.