Nissan dealers recommend replacing the air filters every 12-15k miles on the Nissan R35 GT-R. Cost: ~$150. With these HKS drop in filters, you can easily replace your filters on your own, AND save yourself some time and coin.
HKS Super Hybrid Filters are high performance air filters that drops into the stock factory air intake box with no modifications. This filter features a 2-layer wet-type polyurethane material that is bonded to a flexible nylon frame. A perfect affordable upgrade for those who wishes to keep the engine low profile and much more price friendly from a full intake system that requires removal of the stock air intake box.