Direct-fit aftermarket air filter for Troy-Bilt small engines and outdoor power equipment. Built to OEM specifications for easy installation and reliable performance.
Fits These Models
Troy-Bilt 11A
Troy-Bilt 12A
Troy-Bilt 21C
Troy-Bilt 24A
Troy-Bilt 24B
Troy-Bilt 491588s
Replaces OEM Part Numbers
399959, 1904481
Fitment tip: Always verify your engine or equipment model number against the list above before ordering. Questions about compatibility? Contact us — we're small engine parts specialists.
