There are two modes in which you can view a BOM structure in the EBOM tab,
Instance mode and Quantity mode. The two modes affect how parts with the unit of
measure 'EA (each)' appear in the BOM (parts with other units of measure are not
affected). With design collaboration applied to the BOM, the modes also affect how the
BOM structure and Product structure are updated when a part is added or removed.
Note:
Quantity mode is turned on by default and only an administrator can switch to
Instance mode.