ORD: The quantity of parts being ordered. If parts are being returned the quantity must be entered as a negative number.
ISS: The quantity of parts that the system can issue (based on availability).
SHP: The quantity that will be invoiced (and possibly shipped) when the sales order is next invoiced.
INV: Indicates the quantity of the part that will be processed by the next sales order billing run (i.e. the currently invoiced quantity)
Note: The difference between the ISS and SHP is the quantity already invoiced. Example ISS = 5, SHP = 2. This means 3 were already invoiced and 2 will be billed on the next invoice. After the parts billing run has processed the line item, SHP and INV will be reset to blank.