Nylon 66, also referred to as nylon 6-6, nylon 6/6, or nylon 6,6. Nylon 66 is an amorphous solid that has excellent abrasion resistance, high melting point, high tensile strength, high dimensional stability, high lubricity, resistance to hydrocarbons, and photo degradation, as well as exceptionally balanced strength, ductility, and heat resistance. It is very resilient, waterproof in nature, and slightly soluble in boiling water, difficult to dye but possesses high colorfastness and not easy to fade.