Shock absorber valve discs require an exceptional level of reliability and outstanding fatigue resistance.PATURLE ACIERS CP-Flex 25 ® ™ is immaculately crafted carbon steel with close tolerances, very high mechanical strength, outstanding fatigue resistance and perfect flatness. For application requiring extremely high resistance to fatigue, Paturle Aciers offer the S-Flex25, a stainless steel with a high level of Molybdenum to offer exceptional resistance to fatigue.