Made of acetal polymer. Holds tissue specimen during the embedding process, as well as in a storage file. Molded from a special high density polymer. Keeps 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. Just snap apart and conveniently lock the lid into the base of the cassette. They can be opened or closed as often as necessary and they always relock securely without danger of specimen loss. Large labeling areas are located on three sides. Anterior writing area at a 30 angle.