A mantrap is a mechanical physical security device for catching... - dofaq.co
mantrap (snare)

A mantrap is a mechanical physical security device for catching...

wikipedia - 10 Jul 2015
A mantrap is a mechanical physical security device for catching poachers and trespassers. They have taken many forms, the most usual being like a large foothold trap, the steel springs being armed with teeth which met in the victim's leg. Since 1827, they have been illegal in England, except in houses between sunset and sunrise as a defence against burglars.

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