Abstract: A hydro-elastic support mounted between two mechanical elements, subjected to excitations of variable frequencies, and able to provide two levels of stiffness by simple outside control includes an elastic vault adapted to be fastened to one of the mechanical elements, a support adapted to be fastened to the other mechanical element, an upper fluid chamber, a compensation chamber limited by a membrane, a helical duct providing a communication of the fluid between the two chambers, and a central piston for compensation of movement of the fluid from the upper fluid chamber to the compensating chamber. The piston can be immobilized by any time by an integrated mechanism that can be controlled remotely.