The maximum fatigue life is 2 million cycles. The gas spring after two million cycles may still work, but we have defined it as "expired" and will not be suitable for continued operation and should be replaced. All nitrogen gas springs include a two-year quality guarantee or a 100,000-meter travel guarantee. All nitrogen gas springs are produced to the highest standards to meet the high requirements of the metal pressing industry. All of our cylinder pistons are produced in accordance with the ISO9001:2008 quality certification system and meet the requirements of EU pressure equipment.