I find the hotter it gets, the the better it works at keeping insulin stable.. They work! & i've flown to hot destinations with a rock band & the wallet has also stood up to the rigours of gigging.
The reports by Amazon users that they "leak gel, that they get the pens gooey, and that when wet, they swell up and are difficult to get back in the case.?" That
@Sugar High reports.
hmmmmm.
Probably "user error." regarding over soaking the product by going beyond the recommended period of submersion in water..
The idea behind any product designed to keep insulin at a safe temperature in the extremes. Is to stop your meds becoming dysfunctional by spoiling..