aFe 21-91070 Magnum FLOW Pro DRY S Air Filter Oval 5.25x7 in Inverted Top 8 in

Vehicle Fitment

• Universal replacement air filter for aFe POWER Magnum FORCE intake systems specifying this oval dual-dimension conical filter geometry
• Compatible with any intake system or housing using a matching (5-1/4 x 7)-inch oval flange inlet - confirm dimensional compatibility with your specific application before ordering

Fitment Notes

• The 21-91070 uses a dual/oval cross-section conical format - the (5-1/4 x 7)-inch flange is an oval/rectangular dual-dimension opening, not a round circular inlet. Confirm that your intake system uses this specific oval flange geometry before ordering.
• The filter features an inverted top design - the (4-1/2 x 6-3/4)-inch top opening is inverted (larger than might be expected in a traditional tapered cone), which provides more usable filter media surface area at the top of the filter, resulting in longer service intervals between cleaning cycles.
• This is the Pro DRY S oil-free version - no filter oil required at installation or after cleaning.
• Sold individually - one filter per package.

Features

• Pro DRY S Three-Layer Oil-Free Synthetic Media - 99.2% Filtration Efficiency: The 21-91070 uses aFe's Pro DRY S filter media - three layers of progressively finer mesh oil-free synthetic material. The progressive three-layer construction delivers 99.2% filtration efficiency and consistent high airflow performance even as the filter accumulates contamination between cleaning cycles. No re-oiling required after cleaning - maximum maintenance convenience for street and light off-road use.
• Large Oval Dual-Dimension Conical Design - Maximum Filter Surface Area: The (5-1/4 x 7)-inch oval flange expanding to a (6-3/8 x 10)-inch base across 8 inches of height provides a very large filter media surface area - well matched to the high airflow demands of the Magnum FORCE intake systems this filter is designed for. The large oval base substantially increases the filter face area compared to an equivalent round filter, supporting higher airflow volumes.
• Inverted Top Design - Extended Service Intervals: The inverted top - where the top opening is (4-1/2 x 6-3/4) in rather than closing to a sealed cap - exposes additional filter media surface area at the top of the filter for incoming air to pass through. This inverted design effectively increases total usable filter surface area, extending the dust-holding capacity and service interval between cleaning cycles compared to a closed-top conical filter of equivalent dimensions.
• Tall Open Evenly Spaced Pleats - Outstanding Dust Holding Capacity: The tall, evenly spaced pleats across the 8-inch filter height maximize media surface area and dust-holding capacity - maintaining airflow performance over extended service intervals in demanding intake applications.
• 100% Polyurethane Top and Base Frame: The full polyurethane top and base frame maintains its shape and sealing dimensions across the full engine bay temperature range - resisting degradation from heat cycling that affects other materials over time.
• Pliable Polyurethane Flange with Integrated Bump Seal: The pliable polyurethane flange with integrated bump bumps creates a tight, no-leak seal against the intake housing over the life of the filter - without sealants, gaskets, or tape.
• Washable and Reusable: Clean with aFe's Power Cleaner (PN 90-10601), rinse, and allow to fully air-dry before reinstalling - no re-oiling required.

Specifications

• Part Number: 21-91070
• Brand: aFe Power (Magnum FLOW series)
• Product Type: Pro DRY S Replacement Air Filter - Oval Dual-Dimension Conical, Inverted Top
• Filter Media: Pro DRY S - Three-Layer Oil-Free Synthetic
• Flange / Inlet F: (5-1/4 x 7) in - oval
• Base B: (6-3/8 x 10) in
• Top T: (4-1/2 x 6-3/4) in - Inverted
• Height H: 8 in
• Filter Style: Oval conical, inverted top
• Frame Material: 100% Polyurethane (top and base)
• Seal: Pliable polyurethane flange with integrated bump seal
• Oiling Required: No (Pro DRY S - oil-free synthetic media)
• Washable / Reusable: Yes
• Filtration Efficiency: 99.2%
• Fitment: Universal (by flange dimension compatibility)
• Quantity: 1 (sold individually)

Included Components

• 1x aFe Magnum FLOW Pro DRY S Oval Conical Air Filter (21-91070)

Product Description

The aFe 21-91070 is a Magnum FLOW Pro DRY S replacement air filter in a large oval dual-dimension conical format with an inverted top - designed for aFe Magnum FORCE intake systems requiring the (5-1/4 x 7)-inch oval flange inlet. The large (6-3/8 x 10)-inch base and inverted (4-1/2 x 6-3/4)-inch top across 8 inches of height provide exceptional filter media surface area, delivering the high airflow volumes and extended service intervals needed for performance intake applications.

The Pro DRY S three-layer oil-free synthetic media achieves 99.2% filtration efficiency without requiring filter oil - ideal for MAF-equipped engines and for owners who prefer a simpler, no-oil maintenance procedure. The inverted top design exposes additional filter surface at the top of the filter for increased airflow capacity and longer dust-holding service intervals. Pliable polyurethane flange with integrated bump seal provides a no-leak connection without sealants. Washable with aFe Power Cleaner. Universal fit for matching oval flange dimension applications. Sold individually.