MED PRIDEReusable Hot and Cold Gel Pack Microwaveable Hot Gel Bag with Cold Therapy Belt for Pain Relief Includes Two Gel Packs

the freezer packs stay nice and flat and remain reasonably flexible when frozen - I got these to use after my allergy immunotherapy shots - ice helps the intended allergic reaction at the shot site (I get two shots one in each arm, so ordered 2 sets) - the packs get COLD - they form around my upper arms and are a bit stiff when frozenI need to make sure I've got fabric between the fabric pouches the ice packs go in because they are too thin to be used alone and so I've given myself light cases of frost burn a couple of times. This is something to be aware of if intending to use as cold packs for therapy or injury - but these packs will be EXCELLENT for using in a cooler to keep food cold because they stay cold forever at room temperature - easily 4 hours - in a thermal bag you'd probably get a good 8-10 hours (I should test this with one of my lunch bags) with a long sleeve tshirt I'm able to wear the ice pack for what I intend to be 30 minutes (often ends up being 45-60) - take it off for 20 - and wear it for another round before needing to put back into the freezer - I could probably do another round before needing to refreeze - but half the time both of my supposed to be 30 minutes will often end up being 45-60 minutes because the lack of itching feels good and I don't hear my timer actually go off to take them off. so they're probably out of the freezer for close to 3-4 hours - and are still frozen, but very flexible so I can tell they're warming up - so at this point I just switch to the other two that are in the freezer (the nice thing about each set coming with two ice packs)another thing to note - the elastic is set so that the velcro grabs onto the thicker fabric side - if it were the other way around - or both sides of the pouch were the same thicker fabric - probably would not need to have an additional layer of fabric between my skin and the pouch holding the ice pack.for an idea on sizing - my upper arms are about 17.5 - 18 inches wide and there is a bit of room for it to fit larger and still have good compression without over stretching the elastic

Product great but package came completely flattened and but oh well works good

It exploited in the microwave after 35 seconds. Luckily I have a 2nd one.

These are easy to use and wearable while you continue to move around.

I got these after I had surgery to help with the swelling. They stayed on all night while I slept.

Can be used hot or cold.

Easy to use

I used these as a hot pack to relax my elbow joint and muscles prior to doing my exercises. BOTH of the gel packs leaked after 3 uses. Additionally, unlike the Q&A answer, it stays hot for around 10 minutes, warm for 30, NOT an hour. Waste of money, bad for the environment.