It takes just 5 minutes to get an accurate result from this simple to use, one step, non-invasive drug test kit. Elevated levels of urinary/saliva metabolites are found within hours of exposure and remain detectable for between 3-10 days after smoking. The test panel yields a positive result when the concentration of THC-COOH in urine usually exceeds 50 ng/mL and in saliva 12 ng. Kit includes 1 testing unit.