Hopefully not too basic a question. I am replacing my old pneumatic brad nailer and stapler. The new ones are Senco for the nailer and Porter Cable in the small crown size for the stapler. They are enroute and haven't arrived yet. I want to buy a supply of brads and staples for them. I don't know if my existing supply will fit them. What do I need to know about fitting brads and staples to these units? Do I need to by the same brand? Are they all the same and it doesn't matter? Thanks for any help.