Patent ID: 7771992

Claim:
A system of stackable tissue processing cassettes comprising: a first cassette, the first cassette comprising a bottom wall, a front wall, a back wall, and two side walls with the bottom wall, the front wall, the back wall, and the side wall forming a first container having a top opening, wherein a histological specimen can be placed within the first container through the top opening of the first container; and a second cassette, the second cassette comprising a bottom wall, a front wall, a back wall, and two side walls with the bottom wall, the front wall, the back wall, and the side wall of the second cassette forming a second container, the bottom wall of the second cassette includes a plurality of apertures extending therethrough, wherein the first cassette can be interlocked with the second cassette such that the bottom wall of the second cassette closes the top opening of the first container to prevent the histological specimen from exiting the first container, wherein the plurality of apertures of the bottom wall of the second cassette allow liquid paraffin to flow from one of the first and second containers and into the other of the first and second containers while the first and second cassettes remain interlocked.