How to test HEROIN (opioids)?

How to test heroin & opioids: if you intend to use heroin or other opioids, first you need a heroin test kit to check it for adulterants. Pure heroin can look brown, black or white, and can’t be identified by appearence. To test heroin use reagent tests Marquis, Mecke and Froehde in single-use or multiple-use test kits. To detect fentanyl or test for fentanyl analogs it’s recommended to use fentanyl test strips.