I used to purchase the 3000 yard spools of the Trilene XT green I've used forever and it's a rare season that I would go through an entire spool, so I don't think you have anything to worry about. Some spools of the lesser used lb test might take years to be used up and I never had a problem. Now I can't say that for all lines, some of which never worked well from the get go, like Berkley Sensathin. If you've used the line before, I wouldn't be concerned about it's age (to a point), as long as it's not been sitting on someone's car dashboard

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