Type 6,6 Nylon, or Nylon 6,6, is a synthetic thermoplastic polyamide, whose fiber form is widely used in commercial carpets. Unlike Type 6 Nylon, it has a molecular structure comprised of two monomers—adipoyl chloride and hexamethylene diamine—each containing six carbon atoms.The fiber comes in two forms—filament or staple—and is often extracted and used to create products that require flexibility and durability. Type 6,6 Nylon has a denser, more crystalline molecular structure, higher melting point, and slower permeability compared to Type 6 Nylon, which makes it more stain-resistant and ideal for commercial carpet applications subjected to harsher high-traffic conditions. Its high tensile properties, elasticity, excellent colorfastness, and fiber strength make it the most common used fiber in the commercial carpet industry, along with Type 6 Nylon.