Abstract: This subjecting mechanism is a versatile mechanism which allows to locate different postural supports or accessories such as lap-tray desks, umbrellas, fishing rods and virtually any other desired accessory, in various points of a mobility system on wheels or on rest, with easy fastening and release. It allows to locate the postural supports in accordance to the user's need with more than two degrees of freedom. The subjecting mechanism may work as a unit or in combination with two or more clamps for more stability, and may even be fastened with belts or lariats that bring other points of support. The connecting postural supports present in this invention are modular structures, where the base of the structure may be smooth, with setoff or a protrusion net lower part, lending support to all the upper limbs to perform different manual activities.