Hydroflask Stainless Steel water bottles have been in our shop now for a couple years. They are double wall insulated 18/8 stainless steel bottles that are all bpa free. They aren’t like your regular water bottles in that they are insulated like a thermos… but they aren’t bulky like your typical thermos either.
With myself being the eternal skeptic, I had to put the “keeps things cold for 24 hours and keeps things hot 12 hours” slogan to the test. I loaded the bottle with ice cubes and water and put it in my car the night before I was headed out to the Gorge on a day with the heat index around 100 degrees. The next evening after leaving the bottle in my hot car all day without the windows cracked, I was pleasantly surprised when I picked up the bottle to hear ice still slushing around inside the bottle. Needless to say, I was thrilled to have something cold for the drive back to town.
When I tried the 12 hour hot test, I got a little bit antsy about it and paid the price with a burnt tongue. Any true coffee addict knows that you can’t have coffee 12 hours without drinking it. Since temptation consistently messed up the results of this test I’ll give you my best test results to date. I took my coffee and poured it from the coffee maker into the hydroflask and sealed it immediately. I decided after an hour of trying to sip it to leave the lid off. The coffee stayed piping hot with the lid off from 8:30 am until noon when it finally cooled down enough to polish it off. Bottom line, I think this could handle 12 hours sealed, no problem.