When new and with no long term testing I believe they "speculated" 10 years was the useful life. As the early bags approached the 10 year mark the expiration date was extended to 15 years. I'm confident and betting they will deploy as designed when they are well past the 20 year mark, probably longer. Remember, these are pretty much sealed and not exposed to the steady UV bombardment (unless they are exposed through oh say and opening in the cover )which would degrade the bag material/ More likely a badly worn set of slip rings will prevent deployment before the bag itself fails.

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Mike Tangas
'73 280SEL 4.5 (9/72)- RIP
Only 8,173 units built from 5/71 thru 11/72

'02 CLK320 Cabriolet - wifey's mid-life crisis

2012 VW Jetta Sportwagon TDI...at least its a diesel

Non illegitemae carborundum.