Features: Dual stage foam: Two different pore sizes create more trapping area for even the smallest dust particles Flame laminated foam: Both *stages* are not glued, but heat sealed to provide maximum air flow Reticulated foam: Increases dirt stopping surface area and increase foam strength Strongest glue seams will withstand harsh solvents and gas (although we can*t understand why you*d want to use them). Pull as hard as you can, foam will rip before the glued seam will Light color foam easier to spot where the filter oil has covered and where it has not OEM size for more dirt stopping capability Handmade Every square inch of each filter is and inspected for quality One year warranty Made in the USA, not a cheap Chinese throw away