Molded from a special high density polymer, these cassettes keep specimens safely submerged in liquid and are totally resistant to the chemical action of histological solvents. The efficient flow-through slots maximize fluid exchange and ensure proper drainage. The one-piece integral lid eliminates the need for separate steel lids. The snaplatch and hinge-lock design of the UNISETTE prevent early separation of base and lid and allows for one-hand operation. 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 two sides of the cassettes. Anterior writing area is at a 35° angle.