We just used the 32 oz version to transport and keep cool perishable juices during a backpack in the Haleakala crater on Maui. Two days later the contents were still cold. (We pre-chilled the bottles and added ice, both of which are essential.)
I'd been hoping for a 40 oz version for full-day hikes in hot weather. A pair of 40 oz bottles would be adequate for a Whitney day hike, and would provide cold liquid in the afternoon when the tempeature is high.
The next size that I hope to see in a lightweight wide mouth version is a shorter version of the 24 oz, something with a capacity of 16 or 17 oz. Tall bottles tend to fall out of the pockets on backpacks and hydrations vests. A shorter bottle, that could be refilled from a larger bottle kept inside the backpack, would be ideal.

Sent in my old Hydro Flask for a replacement one. Received the same color and size, but the latest version with the Flex Straw Cap. I think the caps are better than previous versions, but the straw tends to be looser and tends to pop out more. Overall, still love the Hydro Flask brand. My last one lasted 6-7 years and went through lots of drops and dents, as it lost its ability to maintain the ice cold drinks cold for long periods of time. I have the same one in multiple colors now, but very happy that Hydro Flask fulfilled my trade in.

I don’t even remember when I bought my first forty-ounce Hydro-flask bottle; however, I know it was over 10 years ago. Way back I had broken the lid a couple times, made the call and they mailed me new lids,… no problem. When they changed the warranty process and made it a little more complicated, I put the bottle on the shelf for quite a few years. Recently, I broke out and wanted to use it, again, so I made the call. After an initial back-and-forth mis-communication, they sent me a couple of lids. But… they didn’t fit. They changed the style. So, I called back and was informed that the bottle was so old that it had a different cap thread. Customer Service sated they would simply honor the warranty and give me a whole new bottle. I am impressed. I am old-school and value when a company stands by their professed warranty. As so many things in the world are going south, it’s nice to know that Hydro-flask is still on the up and up. Thanks.

I love everything about this insulated water bottle! It keeps my water cold for hours, the straw cap easily flips open and closed, the small loop on the cap allows for easy grabbing with your finger, the wide mouth makes adding ice simple, and it’s fits in my car cup holder unlike other large water bottles I’ve tried. I’m not sure if it’s dishwasher safe but I have used in the dishwasher a few times without issues. What’s most important to me is that it hasn’t rusted or molded on the inside after using for over a year. I’ve paid more for another stainless steel water bottle from a well known company and didn’t realize that white and black spots were accumulating inside; the mouth was so narrow, it’s not something you can easily see. Needless to say, I replaced it with this Hyrdo Flask and it has exceeded expectations. .