Recently I saw a comment about Frio Bags on survivalblog. This led me to do some research on them. They are manufactured by the Frio Company and are sold as Insulin Cooling Cases. The Company claims they provide a highly effective, yet low-cost solution to the problem of keeping insulin at a safe temperature without the need for ice packs or refrigeration.
The principle is simple. To activate the case, immerse it in cold water for 5-15 minutes. Crystals contained in the panels of the case then expand into a gel, which remains cool for several days. The process of evaporation is relied on for cooling. Just wipe dry the outside of the case and it’s ready to use. To reuse it again, just put the FRIO® case back in water and it can be reactivated over and over again.
The Frio website states “FRIO® wallets keep insulin safe for a minimum of 45 hours (more than 5 times longer than an ice pack) — even in constant environmental temperatures of 100 degrees Fahrenheit!”
The website can be seen at the following link. https://www.frioinsulincoolingcase.com/index.html
I don’t know how effective these would be to keep insulin cool for a number of years. However for temporary storage or for use in a bug out (72 hour kit) bag I think they would be very usefully. They come in different sizes and some of you may think of other possible applications.