Abstract: The subject matter of this invention is a telescopic actuator with tubular cylinders which at the same time function as pistons, used to move/shift/translocate pieces of devices especially while emergency opening damaged movable elements/components. It has a bushing body (1) connected with a head (5) attached to its free end and the head has a control segment (10) and the systems feeding the actuator with pressure agent/factor, created in the form of at least one gas generator (9); and by the fact that the bushing/sleeve body (1), the first cylindrical piston (2) and another cylindrical piston (3) have at least one ring groove situated on the surface mating with another tubular element near the head faces of those tubular elements.