Looks to me like a small silicon vacuum mold tool, used for producing one-off prototype or ultra low volume parts. You can usually get 5-10 parts out of a silicon tool, depending on the complexity of the part, before the silicon starts to break up. The tool is made by casting a silicon resin around a master part, that has usually been rapid prototyped, then the tool is split and the master removed leaving the cavity to be filled with a plastic resin.
