The material used for the sealing lip is a mixture of one or more basic elastomers and a variety of ingredients, such as: reinforcing fillers, plasticizers, antioxidants, accelerators, etc. This is for the purpose of providing it with certain properties, such as:

• Compatibility with the fluid contacted
• High degree of elasticity
• Wear resistance
• Low friction coefficient.

A familiarity with the materials is essential to help the designing specialist make the proper selection of the most suitable materials for the application of interest.