Some users create different part numbers for the same part, but used by different customers. Others take advantage the ability in Manex to identify AVL requirements by specific customers without creating multiple sets of part numbers for the same part. This has the advantage of having all requirements under one part number, and avoiding excess inventory because of the likelihood that some of the part numbers will be forgotten when they could be used for a new requirement. There is also provision for a customer to eliminate a specific AVL for a part associated with a specific assembly.