To use one of these we need to establish a part of a room that we do not usually use, and we must have approximately a measure of 25 x 25, that is, a square. We can not condemn it to a corner as we need to have availability to observe all parts of the object, both behind and in front and also the sides of it. To measure the height we will need to do it in a U-shape as these are the universally accepted measurements. The models that we have for sale and are the most purchased are the 21U, which houses small devices, 35U or 36U which has an intermediate range of devices, and the largest, or full size: 42U-.