Don't know, ~3yrs, they are in a bunch of rigs I wheel with, so far all good. The way I see it, at ~$125 they are disposable, even if it needed to be changed every 5yrs, would always have a fresh core and that is better than an old partly clogged, expensive core?
that's the price range for that 1918; so it must be that one. It depends when and where it fails thought but not a bad point.