The K&N RU-3110 is a round tapered universal clamp-on air filter built on cotton gauze media and sized for a 4.5-inch flange, a 5.875-inch base, and a 5-inch rubber top. The manufacturer's listing gives it a 3.25-inch height. Because this is a universal design rather than a vehicle-specific part, the flange opening has to match your intake tube, so measure before you buy. Compared with a disposable paper element, the manufacturer describes this line as a washable reusable filter, which makes it a longer-term purchase for track, drag, and off-road builds that see heavy dust. Its pliable rubber flange absorbs vibration and allows for secure attachment, which helps it hold its seal on a rough intake.
Searchers looking for a 4.5 inch flange universal cone filter, a K&N RU-3110 intake replacement, or a reusable cotton gauze cone for a custom cold-air or short-ram setup will find this part matches that description. The manufacturer notes that regardless of the angle or offset diameter of the air intake, its universal line is meant to cover many setups. Its flange can stretch up to 1/16 inch (1.5 mm) to fit in between sizes, but that allowance is small, so it does not replace choosing the correct diameter.
The manufacturer lists this as a universal clamp-on filter, so it is not built for a specific vehicle. Fit depends on whether the 4.5-inch flange matches your intake tube's outside diameter, along with the base and top dimensions.
The manufacturer states the flange can stretch up to 1/16 inch to fit in-between sizes. Owners on user forums warn that forcing a flange onto a tube that is too large can stress the rubber and lead to failure, so the correct size is the safer choice.
The manufacturer says K&N universal filters are washable and reusable. Its listed re-oiling amount for this part is 0.52 oz (15 ml).
This is a clamp-on swap rather than a bolt-in job. The manufacturer's general air filter guidance notes that a K&N filter does not require a specific installation procedure, but a tight intake tube or a stiff airbox lid can make seating it harder. Disconnecting the intake tube from the airbox lid can make the lid easier to manoeuvre, and holding the filter in place with your fingers while seating it helps keep it from falling out. Confirm the flange seats fully on the intake tube before tightening any clamps, and do not stretch an undersized flange onto the tube to force a fit.
