Justamente se describe en la página
Vibb eaters..and what they do !
If you remember your basic Physics lessons you will know that you cannot get rid of energy but simply convert it into another form. This is a fundamental law of physic's and of course nature. We have choosen a route that converts un-wanted energy into heat, as this is the least harmful to our precious musical signal.
‘Vibb eaters’ consist largely of our own dedicated copper-based sand mixture with the addition of small quantities of, amongst other things , specific precious metals. The properties of this mixture offers very interesting characteristics, particularly in the areas of magnetic fields, field effects, as well as dealing with physical vibration & surface energy. When you place a ‘Vibb eater’ on top of your loudspeaker speaker or on top of your electronic equipment the vibrations and various magnetic fields that come from the box's are absorbed, then through the mechanical friction between the copper granular mixture the excess energy is converted into very low level heat.
It's easiest to experience first hand the effect Vibbeaters have on your speaker by simply placing one ( there are a number of different sizes & weights for different speaker or electronic's cabinets) on top of your speaker while music is playing through them. Placing your hand on the speaker you should find that it is now almost free from vibrations but If you then move your hand/fingers and touch the ‘Vibb eater’ you will sense a great deal of activity, especially near the very top of the Vibbeater.
Guess where all the energy has gone ?
O sea, me recuerda las bolsitas con piedras que se colgaban el los cable de audio, y en este caso, pues simplemente se colocan encima de las cajas de los parlantes o por alrededores, para absorver las "malas vibraciones y/o malas energías" o algo así
Me imagino que poco importa lo que contengan las bolsitas, e incluso puede que sea un verso la descripción de la página

.
El timo es demasiado evidente, pero esta claro, que se produce dado que lo siguen comprando

Y lo mejor, teniendo en cuenta el precio de venta y el costo de manufactura, que no creo que sea para arruinarlo al vendedor
Me hace recordar, si me permiten en offtopic, alla a mediados de los 90, cuando vi por tv que un tipo de lleno se guita vendiendo latas de aire de diferentes partes del mundo (según él), y quede alucinado al ver que lograse vender eso.