PUR exclusive enhanced HVAC filters up to 99.7% of dust, pollen and contaminants, PUR exclusive weaves are USA-engineered to last up to 15,000 miles, 25% longer than standard performance of 12,000 miles, PUR filter use thick, industrial strength electrostatic media to trap even the tiniest of particles while densely packed activated carbon prevents gases and odours from entering the cabin, Road debris, exhaust fumes, and contaminants undergo filtration through a three-layer system, which includes a dust filter for trapping road debris, a particle-averting filter to block airborne particles, and an adsorption filter for absorbing exhaus, Contains soda combined with carbon cleans the outside air flowing through the ventilation system, Part Reference Numbers : 504496 XC10257 CF12527 CF1284 PC9954 TC51395 C51395 WP10263, Kit Includes: 4x Cabin Air Filter, Kit Variations: K54-100138 K54-100279 K54-100428 K54-100650 K54-100781 K54-100940 K54-101099 K54-101258 K54-101417 K54-101576, Part Reference Numbers : 504496 XC10257 CF12527 CF1284 PC9954 TC51395 C51395 WP10263