# Do heat packs have a shelf life?



## a Vertigo Guy (Aug 17, 2006)

Because I had used some yesterday and apparently they didnt work (found out post delivery). Luckily the frogs shipped safely but I dont need more close calls.

-C


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## Pumilo (Sep 4, 2010)

Yes they do. It should be stamped on the plastic package. Additionally, they should be "soft" and pliable, as if it is filled with dirt or sand. If it is hard and doesn't bend, it is compromised and should be discarded.
Additionally they need to breath or they cannot function.
If your box is not insulated well enough, they may not seem to be working. You also need to make sure it is rated for long enough. Hand warmers won't cut it. You need something like 40 hour or better.
One more thing, I would NEVER use less than a 40 hour pack myself. Packs with a shorter rated time period, get hotter than longer rated packs do. Shorter time packs may cook your frogs, then deplete themselves, eventually arriving at their destination frozen.


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## us13fox (Jan 12, 2013)

I am 90% sure they do its normally labled on the package stamped into the foil so it can be hard to make out. I can see if i can find mine and take a pic so you can see it. Like most things though the chemicals have a shelf life but can also be activated accidently (i have had that happen a few times).


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## dartsanddragons (Jun 6, 2004)

I just had several dated Oct 2014 fail to activate 4 out of ten to be exact, I always buy more than I need just in case.


Scott


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## a Vertigo Guy (Aug 17, 2006)

Hmm. These were some Uniheats they were probably several years old. They were still soft like a new pack should be. Either i'll just start buying new ones as I need them


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## Pumilo (Sep 4, 2010)

a Vertigo Guy said:


> Hmm. These were some Uniheats they were probably several years old. They were still soft like a new pack should be. Either i'll just start buying new ones as I need them


Are you also utilizing Phase 22 panels? Heat packs by themselves are much riskier than Phase technology.


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## a Vertigo Guy (Aug 17, 2006)

I used two boxes. Inner box with frogs had two phase packets. Outside I had the two heat packs. The phase packets were crispy so while the frogs traveled ok, it probably got damn cold inside the inner box.


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## Pumilo (Sep 4, 2010)

OK, combos of Phase and heat can be quite useful, but heat by itself is uncontrolled and old school. (for others reading, obviously you've got it)


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## a Vertigo Guy (Aug 17, 2006)

Please explain further. This is my first winter ship. I've only ever shipped during copacetic weather so I've only used phase material during those times.


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