DW-CYD60 for 275N Lifejackets: Deckvest VITO, Deckvest 6D, Deckvest 5D, DURO SOLAS, DURO, DURO+ Spinlock CO2 cylinders do not expire. If there is corrosion on the cylinder, it should be replaced as it may indicate leakage and can damage the bladder fabric. The cylinder's net weight can also be checked for leakage. Please note, this product is unable to be shipped via air freight and is for ground service only.