also to be sure they are 50 state legal they must have a CARB EO number plaque on the actual part. on headers the plaque is welded onto the header with the name of the part.
just as long as it has a CARB plaque or sticker its legal. also when ordering any part verify that the CARB legality marker wether it be a plaque or a sticker is shipped with the part or preatteched. there are vendors, mostly those catering to hondas, that will claim the part is legal or pending approval and ship it without a sticker and promise the sticker will come later. however the sticker never arrives and the part is illegal.