Processing cassettes are made from Acetyl Polymer, which is a special high density polymer that keeps specimens safely submerged in solution. These cassettes are totally resistant to most histological solvents and their slots offer maximum flow through for good fluid exchange and proper drainage. The lids either come attached to the cassette or are packaged separately. The lids can be opened and closed as often as necessary and they always relock securely without danger of specimen loss. Large labeling areas are located on three sides of the cassette for your convenience.