Nylon (polyamide, typically PA6 or PA66) is a tough, wear-resistant engineering thermoplastic with good mechanical strength, low friction, and excellent resistance to petroleum oils, greases, and fuels. It is a cost-effective choice for back-up rings, wear bands, bushings, and guide components in hydraulic and general industrial equipment. Moss Seal supplies both unfilled and filled grades, including molybdenum disulphide and glass-reinforced types for improved wear and dimensional stability. The main design consideration is moisture: nylon absorbs water, which causes dimensional change and softening, so tolerances and service limits are set with the operating humidity and fluid in mind. Continuous service is typically to around 210°F (99°C).