3.5in Flg.-4.625in Dia.- 5.00in L Filter

The 3.5in Flg.-4.625in Dia.- 5.00in L Filter (model RU-3550) is a universal clamp-on conical air filter element designed for custom automotive builds, engine swaps, and performance intake systems where OEM air boxes are removed or relocated. This reusable cotton filter serves as a drop-in replacement or aftermarket upgrade for builders who demand maximum airflow without sacrificing filtration. Whether you're tuning a fuel-injected engine, installing a custom intake manifold, or rebuilding a modified motor, this flange-mounted filter integrates seamlessly into universal intake designs.

The conical geometry and 4.625-inch base diameter maximize surface area for superior air intake while the 3.5-inch flange allows secure clamping to standard intake piping—no modifications required. Constructed from reusable cotton media, this filter element captures particulates effectively while maintaining low restriction; the washable design reduces long-term ownership costs and suits high-mileage or frequently driven builds. The compact 5-inch length fits tight engine bays and custom intake tubes, while the red finish provides visual identification and complements show-quality engine bays. Dense cotton construction offers better filtration than foam alternatives while delivering the airflow characteristics preferred by serious engine builders.

Mechanics and enthusiasts favor this filter for LS engine conversions, street rod builds, turbo manifold installations, and any application requiring a universal intake solution. The reusable element design is ideal for track vehicles, dyno testing, and shops that service multiple engine platforms—one filter specification covers numerous applications. Installation requires only a hose clamp or band clamp on the 3.5-inch flange; verify intake tube diameter (typically 3.5 inches) before ordering to ensure proper fitment and seal.