Yeah design means color, logos etc. As helmets get used they can't require them to use the same one over and over if there is damage or fitment issues or any other issues. I believe this is just about their helmets looking the same all year, not allowing them to change looks. Yet I may be wrong, the NFL is completely stupid, one of the reasons I quit watching it this year. Also I don't know how they would enforce it if it was about wearing the exact same helmet? If it looks identical for the most part I don't know how they would monitor it being the same one. It would have to be a self reporting type thing.