Test kit provides immediate, unambiguous indicators of fuel quality without the need for technical expertise. Simple test is ideal for anyone who uses biodiesel fuel in their commercial or personal vehicles, giving immediate feedback on whether a fuel meets basic criteria for use. U.S.A. Compatible With: Diesel and Bio-diesel, Microbial Contamination Test: Yes, Test Qty.: 6 6 test kits Detects microbial contamination in diesel and biodiesel fuel Identifies fuel that may cause filter plugging and damage to vehicle fuel systems