{"product_id":"k-n-universal-clamp-on-air-filter","title":"K\u0026N RU-5321 Universal Clamp-On High-Flow Air Filter 4.5\" Flange Cone Filter","description":"\u003ch4\u003eVehicle Fitment\u003c\/h4\u003e\u003cul\u003e \u003cli\u003eUniversal Fit - Designed for custom air intake systems with a 4.50 in (114 mm) outside diameter intake tube.\u003c\/li\u003e \u003cli\u003eSuitable for a wide variety of custom automotive, racing, off-road, powersports, agricultural, industrial, and stationary engine intake applications.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch4\u003eFitment Notes\u003c\/h4\u003e\u003cul\u003e \u003cli\u003eThis is a universal air filter and is not vehicle-specific.\u003c\/li\u003e \u003cli\u003eVerify flange diameter and available installation clearance before ordering.\u003c\/li\u003e \u003cli\u003eRequires a 4.50 in (114 mm) outside diameter intake tube.\u003c\/li\u003e \u003cli\u003eMay require modification depending on the application.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch4\u003eFeatures\u003c\/h4\u003e\u003cul\u003e \u003cli\u003eEngineered with high-flow oiled cotton gauze media to improve airflow.\u003c\/li\u003e \u003cli\u003eWashable and reusable for long service life.\u003c\/li\u003e \u003cli\u003eFour layers of premium cotton gauze provide excellent filtration efficiency.\u003c\/li\u003e \u003cli\u003eRound tapered design helps maximize airflow while maintaining filtration.\u003c\/li\u003e \u003cli\u003eFlexible molded rubber flange provides a secure seal and absorbs vibration.\u003c\/li\u003e \u003cli\u003ePre-oiled and ready for immediate installation.\u003c\/li\u003e \u003cli\u003eDesigned to support improved horsepower, throttle response, and engine performance when properly installed.\u003c\/li\u003e \u003cli\u003eHeavy-duty construction for demanding street and competition applications.\u003c\/li\u003e \u003cli\u003eRubber flange can accommodate slight size variations of approximately 1\/16 in (1.5 mm).\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch4\u003eSpecifications\u003c\/h4\u003e\u003cul\u003e \u003cli\u003eProduct Type: Universal Clamp-On Air Filter\u003c\/li\u003e \u003cli\u003eFilter Shape: Round Tapered\u003c\/li\u003e \u003cli\u003eFilter Media: Oiled Cotton Gauze\u003c\/li\u003e \u003cli\u003eFlange Inside Diameter: 4.50 in (114 mm)\u003c\/li\u003e \u003cli\u003eFlange Length: 0.625 in (16 mm)\u003c\/li\u003e \u003cli\u003eBase Outside Diameter: 7.50 in (191 mm)\u003c\/li\u003e \u003cli\u003eTop Outside Diameter: 4.563 in (116 mm)\u003c\/li\u003e \u003cli\u003eOverall Height: 9.50 in (241 mm)\u003c\/li\u003e \u003cli\u003eFlange Type: Centered\u003c\/li\u003e \u003cli\u003eFilter Color: Red\u003c\/li\u003e \u003cli\u003eWashable: Yes\u003c\/li\u003e \u003cli\u003ePackage Quantity: 1\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch4\u003eIncluded Components\u003c\/h4\u003e\u003cul\u003e \u003cli\u003e1x K\u0026amp;N RU-5321 Universal Clamp-On Air Filter\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch4\u003eProduct Description\u003c\/h4\u003e\u003cp\u003eThe K\u0026amp;N RU-5321 is a universal round tapered clamp-on air filter designed for custom intake systems utilizing a 4.50-inch inlet. Its premium oiled cotton gauze filter media delivers high airflow while providing excellent filtration, making it an ideal choice for performance street vehicles, race cars, off-road vehicles, powersports equipment, and other custom applications.\u003c\/p\u003e\u003cp\u003eThe molded flexible rubber flange provides a secure connection while helping absorb engine vibration for reliable performance. Unlike disposable paper filters, the RU-5321 is washable and reusable, allowing it to be cleaned and re-oiled for repeated use throughout its service life. Always verify inlet diameter and installation clearance before installation, as this filter is intended for universal applications rather than direct vehicle-specific replacement.\u003c\/p\u003e","brand":"K\u0026N Engineering","offers":[{"title":"Default Title","offer_id":53362937364799,"sku":"KNNRU-5321","price":94.99,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0832\/7308\/9343\/files\/b59203115a927262f35d0ba9c1fc7a5aL.jpg?v=1780090187","url":"https:\/\/wcaperformance.com\/products\/k-n-universal-clamp-on-air-filter","provider":"WCA Performance","version":"1.0","type":"link"}