Couldn't find any old threads discussing this: How long will a sealed can of new tennis balls last? I've heard hearsay ranging from a couple months to years on end. I plan to order a case or two of balls, but with cold weather/winter coming, I won't use them all up, and I dont want the unused new ones to die out. Thanks for responses! EDIT: Also, is there any sure way of knowing when a can of balls was manufactured/pressureized in a can? Because, for example, if I buy a can in June 2007, it doesnt mean it was made in June 2007. It could've been manufactured/pressureized in 2006, or even before, but was just sitting on the store shelf. So how would one go about being sure a can of balls is "fresh"?