Backup rings serve as supplementary components to primary seals, providing additional support and enhancing sealing performance in dynamic or high-pressure applications. Typically made from durable materials like polyurethane or PTFE, backup rings are installed alongside O-rings or other primary seals to prevent extrusion and maintain proper seal integrity, especially in situations where the primary seal may experience deformation or displacement under pressure. By acting as a mechanical barrier, backup rings help extend the lifespan of primary seals and improve overall system reliability.