PE2500. Prototype version of never seen before medium format Fed-670 camera. Triple format (6x4.5, 6x6 and 6x7) camera with rangefinder and interchangeable lenses. Injection-molded plastic body, MC Helios-113 "Neptun" lens 5.6/65mm. At least 2 prototype samples are known to exist.
Camera below from Ilya Stolyar (USA) private collection.