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: Bio-diesel, Acid Number Test: Yes, Biodiesel Style: B99/B100, Test Qty.: 12 Detects high acid number which is a measure of fuel degradation Identifies fuel that may cause damage to vehicle fuel systems (pitting of fuel injectors)