What does 18/8 Stainless mean?

I bought a water bottle (stainless steel) and there's a marking that says 18/8 stainless on the side next to the volume capacity. What does the measurement mean?
okay fizixx, but what about the other 74%?


Best answer:
Answer by fizixx
If memory serves, this designation represents the amount in % that is Chromium and then Nickel

18% Cr
8% Ni


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