Double pen wallet in use, and wide wallet dryFrio wallets out of my gear box to keep my daily use insulin pens cool. Insulin degrades at heat so it is important to keep it at a temperature where this doesn’t happen, and this is exactly what these do.
They come in a range of sizes to suit, I use the double pen wallet and the wide wallet for storage of spare cartridges. The Frio is a very effective and simple device, you simply drop the inner into water, and the gel pellets swell up retaining the liquid. In the heat the water evaporates and cools the contents using the principle of latent heat of evaporation. Simply, to turn water from liquid to vapour requires energy and that is taken from the contents of the wallet, the insulin and pen, and cools it down. Clever, simple and effective.
Double pen wallet
The wallets are made from a black breathable fabric; breathable to allow the process to work, and black optimises the process by absorbing heat. So it’s best to carry these in an outside pocket, a mesh one is obviously best, if you have them.
I’ve used these on my travels for over ten years now without a problem. The only downside I can think of is having my life sustaining drugs in an outside pocket which could make them vulnerable to breakage. However that is easily remedied by having a spare set carried by someone else, which is sensible at any time of the year – unless of course you’re going solo.
Available here http://www.friouk.com/