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: Yamaha YZ125 1987-1988 YZ250 1987