4into1 Uni Filter 12" x 16" BF-1 65-PPI Green Fine Foam Sheet — 5/8" Thick, Oiled ATV Air Filter Media

The 4into1 Uni Filter BF-1 is a 12" x 16" x 5/8" 65-PPI green fine open-cell polyurethane foam sheet designed for custom and vehicle-specific ATV air filter applications.

This Uni Filter foam sheet gives you a high-flow, fine-pore filtration media intended for trimming or adapting to a wide range of airboxes and aftermarket filter frames. Made from 65 pores-per-inch (PPI) green foam, it’s engineered to hold specially formulated filter oil that captures dust, grit, and debris while still allowing strong airflow for off-road engines. The sheet size and thickness suit many custom projects and repairs where an exact replacement element is not available.

How does this foam sheet trap dirt without choking airflow?

The BF-1 uses a 65-PPI fine open-cell structure that provides many small passages to slow and capture particles while preserving air movement. When the foam is wetted with filter oil, particles adhere to the foam surfaces instead of passing into the intake. The combination of pore density and oil film balances filtration efficiency and engine breathing.

• 65 PPI fine-cell foam for microscopic particle capture
• Open-cell structure maintains high airflow compared to dense materials
• Designed to be oiled for adhesive particle retention
• Thin 5/8" thickness adapts to shallow filter housings

Can I cut and fit this sheet to my ATV or custom filter frame?

Yes — the BF-1 is supplied as a standard-sized sheet so you can trim it to fit uncommon or custom filter shapes. It’s especially useful for builders and riders who prefer to shape the element themselves or need a replacement for discontinued OEM parts. Use sharp scissors or a utility knife and a suitable adhesive or retaining clamp in your housing for best results.

• Sheet dimensions: 12" x 16" for flexible layout options
• 5/8" thickness fits many shallow airboxes and adapters
• Works with common filter sealants, adhesives, or retaining cages
• Suitable for trimming to round, oval, or rectangular profiles

What maintenance and preparation does this foam require?

Before installation the foam should be cleaned of any manufacturing residue, then treated with an appropriate foam filter oil to create a sticky trapping surface. Regular service involves removing the element, washing it in a mild cleaner, allowing it to dry fully, and re-oiling evenly. Avoid over-oiling, which can reduce airflow; follow oil manufacturer guidance for quantity and distribution.

• Wash with soap and water or specialized foam cleaner, then air-dry
• Apply a thin, even coat of foam filter oil to all surfaces
• Inspect for tears or compression; replace if damaged
• Service interval depends on riding conditions and contamination level

Will this sheet work for non-ATV or custom projects?

The BF-1 sheet is intentionally versatile: designers, fabricators, and hobbyists commonly use it in car, motorcycle, and small-engine projects where a custom-sized foam element is needed. Because it’s a universal sheet rather than a molded cartridge, it’s a go-to option for adapting to unusual housings or creating multi-layer filter assemblies for specific performance goals.

• Ideal for custom airbox builds and one-off filter adapters
• Can be layered with coarser foams for staged filtration systems
• Works in many small engines, off-road machines, and prototype applications
• Cutting and shaping allow precise fitment in tight spaces

Who is this for: The 4into1 Uni Filter BF-1 targets riders, mechanics, and fabricators who need a versatile, fine-pore foam element for ATVs, UTVs, dirt bikes, and custom intake projects. It’s suited to people who prefer to tailor their filter shape or combine it with other filter media, and to anyone restoring or repairing machines where an exact OEM replacement is unavailable. If you want a lightweight, oiled foam solution that balances particle capture with airflow and can be shaped to fit, this sheet offers a practical, cost-effective option.