Free Item in Purchase Order Item

Hello All,

I would like to ask where in table level can I identify Purchase Orders which have "Free Item". Because on the screen field i saw from the technical definition that the "Free Item" is of field MEPO1211-UMSON, but when I go to EKPO I cannot find the corresponding field.

I have this idea but I don't know if it is right or not, in case I uncheck the "Invoice Receipt" in the Purchase Order Item details, the "Free Item" check box appears. So I am thinking is all Purchase Order Items which have "Invoice Receipt" (EKPO-REPOS) uncheck considered as a "Free Item".

Thanks.