You can take Todd's advice to the bank. Myself as a former Toyota Mazda shop owner from NEW YORK. TODD HAS SAVED ME MANY TIMES. IM 73 AND RETIRED NOW . P.S. I own two Prius.
They use the same air filter as the regular Prius and Prius v wagon. Brand is not very important on this part. You can find cheap filters on eBay and Amazon that work fine.
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