K&N ATV Air Filter + Oil Filter Combo 1994-2000 Yamaha YFB250FW Timberwolf 4x4 YA-2597 + KN-143 Designed to boost horsepower and rate of acceleration Specifically developed for Off-Road, Motocross, ATVs, UTVs and Side by Sides Pleated cotton media provides a large filtration area offering low restriction, high-capacity and long service intervals Multiple layers of woven cotton gauze media offers excellent filtration Fits directly into OEM air box with application specific sealing bead ensuring a precise fit