Carfentanil Is a very powerful fentanyl-by-product at first circulated within the mid-1980s to be a typical anesthetic for big animals like elephants. Currently, carfentanil continue to sees clinical and scientific use for a radiotracer for positron emission tomography imaging, connected to its large affinity for MORs in brain tissue [14]. https://chemicalglobe.com/product-tag/protonitazene-for-sale-uk/