Abstract: An aquatic exercise device which is to be used within a body of water such as a pool has an element which can be engaged by the foot or hand of an individual, which element is linked to a piston-cylinder combination so that as the user engagement element is moved by the user the piston rides in the cylinder. At the head end of the cylinder there is an opening which provides communication between the cylinder chamber and the water environment. As the piston moves back and forth water is either pushed out of the chamber through that opening or drawn into the chamber through that opening. The size of the opening, which may be selected by the user, determines the degree of resistance to the user's movement against the user engagement element.

Abstract: A coded, magnetic module has a plurality of Wiegand effect exhibiting wires deployed parallel to one another and extending substantially across the module. These wires are supported in a laminated arrangement between two thin plastic support plies. Coding is impressed on the module by punching out an intermediate portion of each wire including the adjacent zone of the support plies. This produces a relatively physically stable coded module for subsequent use as part of a coded magnetic pulse generator.