The materials commonly used in the field of industrial seals (rubber or 'asbestos-free' based on aramid fibers and elastomeric binders), often do not, when used individually, possess the sealing, thickness, chemical and mechanical resistance requirements that certain situations may demand. To achieve these requirements, the seal is wrapped in virgin PTFE, usually 0.6 mm thick (can be modified at the customer's request). The inserts can be in different materials depending on the application requirements. The gasket may also feature a corrugated ring inside the inserts, usually in AISI 316 to ensure maximum resistance to oxidation and mechanical stress, while guaranteeing effective adaptability to any irregularities in the flange surfaces.