5 Pack 491588S Air Filter, Compatible with 491588 4915885 Flat OEM Air Cleaner Cartridge, Lawn Mower Air Filter

What It Is

This is a 5-pack of flat, pre-oiled foam air filter cartridges (OEM 491588S) designed for small engines in lawn mowers, tractors, and zero-turn mowers. It traps dirt and debris before it enters the carburetor, protecting engine life.

Fitment & Compatibility

• Check your engine brand/model: Fits many Briggs & Stratton, Craftsman, Husqvarna, MTD, and Troy-Bilt engines, especially those using the 491588, 491588S, or 4915885 part number. Common on single-cylinder OHV engines (e.g., 500–700 series).
• Measure your filter: OEM dimensions are approximately 5.3” x 4.2” x 0.75” (flat). Measure your old filter’s length, width, and thickness—if it matches, it fits.
• Not for all engines: Does not fit round or cylindrical filters. Verify your air filter housing takes this flat, rectangular shape.
• OEM vs. aftermarket: This is a generic replacement; check that your mower’s model number (e.g., 12A-xxx) is listed in the product description or cross-reference with 491588.

Key Things to Know

• Quality is adequate for the price: Pre-oiled and filters well, but may be slightly less dense than OEM. Change every 25 hours or annually for best protection.
• Installation is simple: Remove old filter, wipe housing clean, drop in new one (no tools needed). Ensure the foam sits flat and the cover seals tightly.
• Common gotcha: Some users report the foam feels thinner than OEM—if your housing has a tight seal, it’s fine. If it’s loose, consider adding a dab of grease to the edges.
• 5-pack value: Great for seasonal replacement or for multiple mowers. Each filter costs ~$1.80, far less than single OEM filters.

Should You Buy It

Buy this 5-pack if you have a common lawn tractor or push mower that uses the 491588 flat filter and want a cheap, reliable way to keep spare filters on hand. It’s ideal for budget-conscious owners who change filters regularly and don’t need premium OEM density. Skip it if your housing has a very snug fit or you prefer exact OEM thickness.