Extruded pile weatherstripping with or without fin is 100% polypropylene and provides a very effective barrier against air, water, dust and noise; sealing against even and uneven surfaces with resistance to abrasion. The pile fibers are resistant to acid, alkaline, mold, mildew and corrosion as well as being silicone treated to repel water. The pile and fins are stabilized to exceed AAMA Class A requirements.