Length:: 1:00 MinsI've put six of these batteries to use. They're all doing fine, albeit it's only been a few days.One of the batteries I took out of the pack registered REPLACE in my battery tester.Maybe I'll get another dud, but at these prices, that's an acceptable failure rate.Nowhere is there an EXPIRATION or USE-BY date. But since the tester registers the batteries to be fully charged, I'm confident they'll last a respectable duration.