The IsInline property sets or returns a Boolean value, which; if True, specifies that the item is inline. This property applies only to Instruments.
When the property is set to True for instruments, then a record will be in the T_InLineComp table when Offline instruments (IsInline = False) have a basic set of attributes.
For Piping Components, the IsInline property in the Catalog Manager Properties window is ignored by the software. It is assumed to have a value of True.