devices are provided for the harmonization of mechanical and electromagnetic oscillations , which include an outer body and an inner body , both having an axially symmetric shape relative to an axis . the inner body may be received inside a first cavity of the outer body so as to be firmly connected to the latter . the outer body and the inner body are made of , respectively , of stainless steel and copper , and may have a weight ratio equal to 3 or the number φ . the dimensions of the device may be such that their ratios are integers , or fractions thereof , or numbers corresponding to powers of φ and / or π .