Abstract: A developer material cartridge including a robust multiple function seal, for use in a developer unit of an electrostatographic reproduction machine including a machine interface member. The developer material cartridge includes a cylindrical housing defining a developer material containing chamber and an open end into the chamber. The robust multiple function seal comprises a single member including a solid first end for sealing the open end into the developer material containing chamber during shipping and transportation of the cartridge. The single member also includes a partially slit-through second end and lead in recess for enabling non-damaging coupling with, as well as puncturing of the solid first end by, the machine interface member, thereby avoiding the undesirable risks of seal damage and developer material spills.