When you define an item or an item–subinventory relationship, you can specify attributes that modify your order quantities. You can use them to model supplier constraints that restrict the size of an order or mandate a specific lot size. You can specify minimum and maximum order quantities and fixed lot size modifiers. For replenishing subinventories, these same order modifiers can be set by item at the subinventory level.

If an order is smaller than the minimum order quantity, Inventory modifies the order upward to the minimum order quantity. Likewise, if the order is larger than the maximum order quantity, it modifies it downward to the maximum order quantity. An order must be a multiple of the fixed lot size multiplier. If it is not, it is revised upward so that the order is such a multiple.