The First Sign drug of abuse cup test is an immunoassay that uses urine specimens to detect the presence of drugs. The test works by allowing a urine specimen to migrate upward on a test strip. If the urine specimen is drug-positive, a colored line will not appear in the specific test line region of the strip. However, a drug-negative specimen will generate a line in the test line region. A colored line will consistently appear in the control line region, signifying that the correct volume of specimen has been applied. This product comes in a test cup format and each box contains 25 individually pouched test cups along with user instructions.