how many hours do they stay cold?
449518
We had them in a big soft cooler bag with snacks for the road for probably almost 20 hours and they stayed cold! They were great once I figured them out!
449519
I have had them on my back or laying on them for well over two hours and they were still cold. I had a three hour drive the other day and had them behind my back, they were still cold when I got there Tip, don't freeze them silver side together, they won't last. It is best if you can freeze them in different parts of the freezer so they don't touch, but I freeze mine white side to white side so the silver side is not touching them.
449520
I have not used them one at a time but two in a cold bag stayed cold 8 hours
449521
It is not that simple. They may stay cold in a good cooler all day, on the table maybe an hour, but on a hot swollen joint maybe 15 minutes. You want cold packs to transfer heat quickly so that they cool things. A better question is how much heat can they absorb? I put it in a cheap cooler with a liter bottle of water that starts at room temp. The bottle of water cools to about 50 degrees after a couple of hours and lasts about 5 hours. Being segmented it has more surface area and transfers heat faster than a solid pack. The solid pack stays frozen longer, but the water does not get as cool. It is not that simple. They may stay cold in a good cooler all day, on the table maybe an hour, but on a hot swollen joint maybe 15 minutes. You want cold packs to transfer heat quickly so that they cool things. A better question is how much heat can they absorb? I put it in a cheap cooler with a liter bottle of water that starts at room temp. The bottle of water cools to about 50 degrees after a couple of hours and lasts about 5 hours. Being segmented it has more surface area and transfers heat faster than a solid pack. The solid pack stays frozen longer, but the water does not get as cool.
777560
It stays longer than 15 minutes. If you keep it in the freezer over night, it will stay frozen all day.
26452
I have fallen asleep with the ice pack next to me in bed and it is still cool 5 or 6 hours later. It is not cold enough to use at that point. I have never had an ice pack that was so terrific.
777561
if you keep ice roller in the freezer over night, it will stay cold for many hours.
445912
Normally I do not have them on longer than 20 min, But they are still pretty cold I would say at 30 min.
1508742
Soak them in water for 20 to 30 minutes. Then freeze them until frozen solid. They work wonderfully. I use them for physical therapy, since they retain the cold for 4-5 hours.
81968
Not likely I would say it stays cold anywhere from 20-30 min tops then you need to throw it back in the freezer to cool it back down, which also takes about 30 min to make it cold again.
371527
I have only used it for cold items. With an ice pack it stays cold for about 6 hours.
2213421
I just leave them in the freezer until we need them. But they should be cold enough within an hour or two.
690230
its insulated but it will only stay cold for about 3-4 hours. ice pack is best
1738382
I've had no problem with them freezing overnight. Time-specific, I am not sure.
1080883
Yes, they definitely sweat. I would say they maybe stay frozen for 2-3 hours. When my daughter brings it home at the end of the day, it is barely cold.
730218
They stay frozen for 20-24 hours; freeze them until hard and they are good to go.
486868
It stays cold for about 4 hours. I used it for relief after achilles tendon/foot surgery and it was so helpful. Would definitely recommend it.
2171551
My husband fills the thermos 1/3 to 1/2 full of ice cubes followed by cold water, and 10-12 hours later when he gets home, some of the ice still remains, although the cubes are smaller. His water stays cold the whole day.
752884
Couple hours at most. It doesn't stay cold all that long, but its ability to wrap is awesome.
1191479
I don't think they would last 9 hours. I use all 4 ice packs with an insulated bag. I even put the bag in the fridge the night before and pack the ice packs before leaving. I've found them still cool after 5 hours, but not enough to help the food.