Can I remove this?

I just received my lipoly packs today, and realized that there is 2 large black squares at the end of the packs. Before i disassemble them and realize i need what ever is there. I need to know if it is just a foam spacer, of if something is accually there. I posted a picture of the areas im talking about. I want to make the packs shorter if possible and removing these would diffinately work.