Universal Air Filters nT 6inH

The K and N Engineering Universal Air Filters nT 6inH (model RU-5173) is an ideal solution for engine builders, weekend mechanics, and daily-driver enthusiasts looking for a reusable, high-flow air intake upgrade. This universal-fit filter effectively addresses airflow restrictions caused by stock paper elements that can hinder horsepower and throttle response, while also requiring frequent replacements.

K&N's signature layered cotton-gauze media, treated with a tacky red oil coating, captures airborne contaminants while allowing for significantly lower restriction compared to paper alternatives—typically improving airflow by 50–70%. The filter features a durable plastic top and base that ensure reliable performance through aggressive intake pulses and temperature changes, making it suitable for various applications including custom intake manifolds and turbo projects.

This filter is particularly beneficial for carbureted restorations and supercharger installations, providing broad compatibility across compact and mid-sized engine bays. Designed for multiple cleaning cycles with K&N's recharging kit, the nT series helps offset long-term ownership costs and waste while maintaining consistent airflow delivery season after season.