A cassette for a waste disposal device, the cassette including an outer wall, an inner wall, a flexible tubing positioned between the outer wall and the inner wall, and a rim having a top surface and a bottom surface. The rim is positioned between the outer wall and the inner wall and extends from a top surface of the outer wall toward the inner wall. The bottom surface of the rim faces the flexible tubing, and the rim includes a plurality of protrusions on the top surface of the rim to engage with a rotation mechanism of a waste disposal device.