Furanyl norfentanyl (hydrochloride) (CRM) (Item No. 19559) is a certified reference material that is structurally similar to known opioids. It is a known metabolite of furanyl fentanyl (Item Nos. 18705 | 19633).1,2 This product is intended for research and forensic applications.WARNING This product is not for human or veterinary use.