Field help (UOMPUUCOE) 

This is the conversion factor expressed between the order unit and the purchase unit (supplier or product).

This coefficient is used to calculate the quantity in PU from an order unit entered in OU:
Qty in PU = Qty in OU * factor
This factor can also be used for the price list conversion into the order unit.
This factor can be accessed if an order unit has been entered with a value different from that of the purchase units contained in the product-supplier or product-master. It is initialized to one of the factors to be found in one of these two files or to the conversion factor table if the combination exists.

You can modify this conversion coefficient if the order unit is a product packing unit, whose coefficient can be modified (see Packing unit table on the Units section of the Product record) but cannot be used with the other units (product purchase unit, supplier purchase unit, supplier packing unit, stock unit).

Inter-company specificities: In the case of an inter-company or inter-site order, the factor used in the generated sales order is always the one entered on the purchase order.