Okay- not forever, but 10+ hours for sure with no protection from the elements.
Sure, you can use them in a cooler for easy cooling without costly bags of ice that only last for a few hours with a few easy steps and a couple of bucks.
We use it for transporting meat and to cool meat rabbits and farm animals during the summer months.
Step 1: Gather Your Supplies
* 3" PVC but any size will do depending on your cooking needs. I got a 12' piece though I only needed to make 7 of them. Too bad I forgot to take a picture before I cut them into 10" pieces.
* 2 end caps (of corresponding pipe size for each ice pack
* PVC glue
* Good 'ol H20.
Step 3: Make Sticky
You might wanna do this outside. It's pretty stinky.
Step 5: Fill 'er Up.
We also added a tiny bit of apple cider vinegar (you could use bleach) just for good measure so the water doesn't get too yucky inside.
We know... If its water tight we will never know how gross it is, but we didn't want to take any chances. This part is not necessary:)