step file conversion does not show some toolbox component?

Hello Everybody,

i have a question about converting assembly to .step file. i have an assembly with parts and sub assemblies, and sub assemblies has toolbox components such as pem stud and strut channel. I saved main assembly file as .step, and opened the .step file to check if everything is alright, i saw some strut channels and pem studs does not shown in the model. i check design tree, 1 assembly look like part and does not have toolbox components, some other assemblies show the toolbox on the design tree (but not on the model). i investigate them maybe they are hidden, but i saw they are saved as parasolid format!! i have no idea how and why this happened.

Is there anybody to help me? 

thank you in advance..

hilal 

SolidworksGeneral