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AFAIK any qualifying vehicle under CA HOV rules can get a sticker...and depending on if and when it was originally stickered you get the red ones (originally stickered 2017 or 2018) or purple ones (never stickered). And as I understand it, there is an extra income test, so vehicles stickered before 2017 (and theoretically not eligible to be re-stickered with a red sticker) can get re-stickered if you meet the means test.