para-methoxy Acetyl fentanyl (hydrochloride) (Item No. 23190) is an analytical reference standard that is structurally similar to known opioids. para-methoxy Acetyl fentanyl is regulated as a Schedule I compound in the United States. This product is intended for research and forensic applications. This product is intended for research and forensic applications.WARNING This product is not for human or veterinary use.