Used in Sampling inspection process in FRIs [ Final Random Inspection].For the purpose of sampling inspection of products AQL is the maximum percentage defective acceptable. When a customer / buyer designates some specific value of a certain defect or group of defects, he or she [customer / buyer] indicates that the level of percent defective in the submitted lots or batches is no greater than the designated value of AQL. Say AQL 2.5, 4.0, 6.5, 10.0. AQL 2.5 means, say in a sampling inspection you accept the lot if the defective goods not exceeding 6 pcs. If defective pcs are more than 6 pcs in a given sampling lot customer will reject the lot.