The Amsterdam is a box in the shape of a cuboid , measuring just enough to hold a person. The interior is often provided with straps in order to limit even further the remaining possibilities of movement of the subject . The walls , then , are provided with small openings to allow to interact amsterdam box with the forced increase and , therefore, its feeling of helplessness . Little is known about its origin , some dare someone derivation with the iron maiden or virgin of Nuremberg, but it is unlikely parallelism. The Virgin of Nuremberg, in fact, is a classic historical hoax : it is a machine that was created at the end of 1700 ( it's not like you think of medieval origin ), probably without a purpose. You do not remember to have been used , nor as an instrument of torture or as a machine to execute death sentences. Of course , there's a song that is named in E.A. Poe, who should refer to the Spanish Inquisition . More simply , the man always tends to lock people into small spaces for a variety of needs , causing side effects such as panic and loss of sensory capacity , that is, sensory deprivation or sensory deprivation. It is therefore likely that its origin , like many other tools BDSM, is to be traced back to that thin line that passes between BDSM and instruments of torture and duress. In the sense that someone, at some time, it must be realized that a person locked up in a tight space causes the "side effects " that add to the simple impossibility of escape. The " victim " , therefore, is forced to immerse themselves in this trunk , tied up and left to "reflect" . In addition, the openings on the walls allow for interaction from the outside and then are added to the feeling of helplessness of the subject against the " jailer " . The greater the time that the person passes in that situation , the greater the effect that is obtained . You pass by the loss of the sense of time to the deprivation of the senses such as sight and touch , which is associated with the increase of smell and hearing . Sensory deprivation joins addition, a change in mental status that may have the most varied effects , depending on the sensitivity of the subject. Not recommended for use , then , to those who suffer from claustrophobia and panic attacks.