What is this apparatus called and what is the technique originially introduced by this apparatus used for?

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Cracked by: Kamal Rathi , Rahulk , Raghuvansh , lordmaldy , varuns88 , Logik , Dibyo , Rogi and Joshan.

Kamal Rathi, Rahulk, Raghuvansh, lordmaldy, varuns88, Logik, Dibyo, Rogi and Joshan