Abstract: The device consists of a container manufactured from a metamaterial with the property of transparency to visible light, for the holding of electrical or electronic devices, which electromagnetically protects the same and renders them electromagnetically undetectable. The purpose of the device is to guarantee user confidentiality in the use of the electromagnetic waves associated with telecommunications, by means of the use of a type of container that encloses any type of telecommunication device or appliance, with the potentiality that the insertion thereof into said container prevents the detection by means of electromagnetic waves of said appliance, and therefore makes impossible the tracing of said appliance by electromagnetic remote sensing means, including mobile telephony, radiofrequencies, or satellite telecommunication means such as GPS, Galileo, or other systems, without it being necessary to switch off said appliance beforehand.

Abstract: An apparatus for grinding solid waste, the apparatus comprising: a first plurality of grinding blades parallel to one another and disposed on a first axle perpendicular to an axis thereof; a second plurality of grinding blades parallel to one another and disposed on a second axle perpendicular to an axis thereof, the axis of the second axle being parallel to the axis of the first axle, wherein the first and second plurality of blades are interleaved and adapted for counter-rotation with respect to each other; a set of gears operatively connected to each of the first and second axles; and means for driving the set of gears to effectuate rotation of each set of grinding blades.

Abstract: This specialized domestic grinding containers system, the manual version of which is completely environmentally friendly, allows us to reduce the excessive amount of varied urban waste generated by daily consumption, using a system of piercing/crushing blades which are set transversely on their supporting shafts and which, when sufficiently locked together, enable waste to be reduced to one-fifth of the initial volume thereof by specially arranging the shafts and using different types of blades and hammers for each type of waste (plastic, cans, tetra bricks, paper, glass, organic material and another combined blade system for reject waste).