Abstract: An extruded thermoplastic product having a surface abrasive to insects. The extruded product is formed from a dry powder composition being comprised of a thermoplastic polymer, a plurality of pelletized diatomaceous earth, and a plurality of expandable microballoons. The composition is mixed and heated in an extrusion machine before being forced into a die of selected profile. Cooling the material immediately after being removed from the die allows the diatomaceous earth to remain at the surface of the material. The material with the surface abrasive to insects is used is used as a component in a product, such as conventional weatherization products, for placement in a building opening that insects use as ingress to the building. Products contemplated for use with the extrusion include door sweeps, door and window seals, and thresholds.