NO TOIL manufactures the world's best 2-stage foam air filters. Using only the best flame-laminated dual-layer foam bonded with the highest quality glue they hand make each foam filter to stand up to the roughest and toughest riding or terrain. NO TOIL filters can be used with NO TOIL biodegradable clean in water cleaner providing the best air filtration system in the world. Fits: Honda TRX350 1986-1987 TRX350D 1987-1989 TRX420FA IRS 4WD RANCHER 2009-2013 TRX420FE FOURTRAX RANCHER 2007-2013 TRX420FM 4WD RANCHER 2008-2013 TRX420TE FOURTRAX RANCHER 2007-2013