NIK Test W Refill - General Screening Test 800. The NIK System of Narcotics Identification is the only international standard for field testing suspicious substances. NIK is also the only field test that has been awarded the ISO 9002 Seal of Excellence for quality control. Using state of the art wet chemistry, the system presumptively identifies the most commonly encountered narcotic and street drugs. Individually sealed NIK Field Tests and Factory Sealed boxes assure propper ampoule placement as well as advanced quality assurance and control.