An evaporative cooling wallet (Frio-style): soak it in plain water and the evaporation keeps the contents cool for up to about 45 hours, with no ice and no freezer.
Last edited · written by PepPrep
No freezer needed
~45 h cool
What it’s for
A cooler that re-sets with tap water, for trips with no freezer. It keeps things cool rather than fridge-cold, and there is nothing to freeze and nothing to melt.
What to check in the listing
Size up — the 'large' comfortably fits several vials plus syringes.
At a glance
TypeCooler
How it coolsEvaporative (water-activated)How it cools is the cooling method. Ice packs need a freezer; evaporative wallets need only water and re-set overnight; powered coolers set a temperature and need charging. Glossary
PowerNone
Holds 2–8 °CNo
Stays cold45 hours
Holds3 vials
Fits pensYes
SizePocket
Needs a freezerNoNeeds a freezer says whether something must be frozen first: ice-pack systems need a freezer before every trip, and hotel minibars rarely count.
Airport-friendlyYesAirport-friendly means it goes through security as carry-on without an argument: no loose ice, no lithium cell above the airline limit, no blades. Glossary
Used forTravel storage, Flying, Long tripsUsed for lists the situations this product is for; the decision tool and the Finder match on these.
PriceMid-rangePrice tier is the rough position within its category, not a live price: budget is the cheapest sensible option, premium costs more for a reason the page explains.
TravelCarry-on friendlyTravel says whether it is practical to fly with: carry-on means it goes through security without fuss.
SterileNoSterile means individually sealed and sterile until opened; anything that touches the inside of a vial or your skin should be.
Pack1Pack is how many come in the listing this site links to; it is shown only where every store's listing gives the same count. Check it against the listing, since photos often show ten and ship one.
ReusableYes
Specifications above were recorded from the Amazon listing on 2026-09-03. Listings change hands: open the listing for its current description, price and availability.