It's a referenced element. For detailed description, please refer referenced element doc. Fulfillment order reverse pick detailed creation information Internal fulfillment order identifier. Service attempts to create reverse pick for the fulfillment order based on identifier. Collection of fulfillment order reverse pick line items. Collection of custom attributes to be updated for the fulfillment order reverse pick. Fulfillment order reverse pick create item information Identifier of the fulfillment order line item corresponding to the created reverse pick line item Quantity in standard unit of measure This type can hold a number of digits count 12. This type can hold a number of digits count 20 and fraction digit count of 4.