[en] The Doublet III facility represents a unique opportunity to convert an existing device to a powerful test bed for FED design and operation issues. Such a conversion is made possible by virtue of the demountability of the devices toroidal field coils. Doublet III can be partially disassembled then reassembled with a large dee-shaped vacuum vessel and associated poloidal coils and structure. Doublet III presently possesses or is acquiring adequate auxiliary heating (14 MW of neutral beams and 2 MW of ECH), stored energy (3 GJ), and power conversion equipment (some added field shaping power equipment is required) to support large dee, reactor-level, plasma experiments. The only modifications required of the device are those directly caused by installing a larger vessel - the vessel itself (and its internal protection system); poloidal field coils that interfere with the larger vessel; and a support system for the new vessel and coils