I have a fairly complex assembly and I am using the Envelope option to exclude certain parts from the mass properties of the assembly.  I'm wondering if there is a way to select only the Envelope parts.  I haven't been able to find a way to do it, even in the advanced component selection tool...so far there doesn't seem to be a way to select based on that criteria.  It's not a deal breaker and I can manage without doing it, but being able to select the Envelope parts may make things easier.  Any ideas?