I bought 5 boxes in early December 2013 & they have a stamped expiration date on each individual light of 09/18. I've been impressed at the duration of lighting being well over the 12hour description! I plan to buy more from Amazon! I've not found a cheaper price anywhere else!!!
By Jeff Pendrey on February 11, 2014
I was in a pitch black room door closed and no windows when I tried it out and I was able to find my locker and see the combination numbers on my lock. I thought it was pretty good. I'm sure you'd be able to see some emergency numbers in your phone book with this product. Hope this helped.
By Mike B on February 17, 2014
They will still work but it may be less effective in colder temperatures. It is recommended to use between 40 to 80 degrees. So even if it gets below freezing they will still be effective once they warm back up. The sticks will freeze around -15 to -20 degrees and will not be as reliable once frozen.
By Jeremy B on October 26, 2014
They are like flashlight batteries, new ones come in and old ones get sold, anyway i believe the last batch I bought from Amazon had a 'Best By' Date of sometime in 2017, it's printed on the outside of every stick on the packaging. I really think they will work well beyond that point anyway if they are stored right.
By Mark from Jersey on December 3, 2012