Magneto-Rheological Fluid (“MRF”) technology has been successfully employed in various low and high volume automotive applications. Good understanding of specific design constraints is required to define and to optimize a magneto-rheological device. This article presents parametrical analyses with magnetic simulations, of a magneto-rheological valve and a magneto-rheological orifice. Experimental rig assemblies of two different control devices have been designed, built and the performances have been evaluated experimentally. Controlled pressure drops, of 0.6MPa @ 4.5A at 5cm³/s in the orifice mode, and 1.5MPa @ 4.5A at 0 cm³/s, in the valve mode, using MRF132-AD, have been achieved. The study shows that excellent features like the fast response and the contactless nature of MRF control are attractive for various control devices.