 The issuing may be used to cover a period of time or to fill a fixed—size container.But unlike the traditional approach, also known as "preproduction issuing" where the costs are assigned to the product order at the withdrawal of materials from the stores and after completion of production any excess material is given back to the stores, backflushing delays that until the goods receipt of the finished product or assembly is issued.The remaining quantity of unused material left on the shops is still held in the system as floor stock and so material will not be ordered incorrectly through the Manufacturing resource planning (MRP).