4-ANPP or N-phenyl-1- (2-phenylethyl) -4-piperidinamine is a new designer drug, classified as piperidinamine. This chemical is synthesized as an intermediate between fentanyl from N-phenethyl-4-piperidone. 4-ANPP impurity which is presncndetn in fentanyl preparations. 4-ANPP is a metabolite of acetylfentanyl, butyrylfentanyl and furanylfentanyl. 4-ANPP produced in modern chemical laboratory, professionals who know their business, which makes it the highest quality.