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Hydro Flask Insulated Wide Mouth Flat Cap - Wide Mouth

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Designed for everyday use, as well as the rigors of the outdoors, our Wide Mouth Flat Caps are insulated to aide in keeping your Hydro Flask contents cold or hot and at the optimal temperature.

The Wide Mouth Flat Cap fits our wide 18 oz, 32 oz, 40 oz and 64 oz Wide Mouth Hydro Flasks. Please note that the Insulated Flat Cap does not fit on the older style Wide Mouth flasks. To find out which style flask you have and whether the Hydro Straw Lid will fit yours, check out the Wide Mouth Fit Guide.

Posted by Francesdunhour on 04/23/2015

5 Star Rating

Replacement lid

Got 18oz as gift lip on lid is cracked need other

Posted by Shelly L on 04/23/2015

5 Star Rating

Can't express how much I LOVE it!

I came to Hydro Flask by accident... I found it in a tote that my son brought home from college. One morning when all my normal insulated coffee cups were dirty, I grabbed this 18oz flask and discovered how amazing it is! Normally, by the time I get to work my coffee is luke warm, but in the Hydro Flask it stays hot - not warm - HOT, no matter how long it takes me to drink it! I've filled it at 7:30a.m. and, after a busy morning, taken a drink at 2:00p.m. and it is still hot. It's like time stands still inside this amazing bottle. Unfortunately for my son, he's not getting it back, and I'm going to order one for my husband and get rid of my cupboard full of other bottles, cups, etc! I think I'll even buy some for gifts so all my friends can clean out their cupboards also! :) Absolutely amazing product. I love it.

Posted by Paul on 04/22/2015

5 Star Rating


Completely awesome produce. I place the mug in the fridge and can dill with an many bears I can drink and they all stay ice cold.

Posted by Deb on 04/20/2015

5 Star Rating

Works as advertised!

This flask actually works as advertised. I work long hours and am usually on the job for 13-14 hours per day with another hour or more of travel to and from work. I take the 40 oz flask to work filled with iced tea and a few ice cubes. The tea remains icy cold throughout my work day. When I get home there will still be ice cubes.

Posted by Nonnie A on 04/19/2015

5 Star Rating

Hydro Flask 18 oz wide mouth

This is the best water bottle EVER!! With kids who play soccer, we have gone through many many water bottles. They would get left at the field, broken when hit by a ball, taken by another player accidently... We found the Hydroflask water bottles and we LOVE them. No other player has the same one, the kids love them and are therefore responsible with them, and they are super durable. I should own stock in the company because I recommend them to EVERYONE. I will never drink from another water bottle!

Posted by Luke on 04/18/2015

5 Star Rating

Firm Believer in Hydro Flask!

Bought my first last summer on vacation in Bend at the urging of the young lady in the rafting office. Glad I made the switch! Used to use Nalgene and will not be going back. Got 4 True Pints, 3 21 oz, 2 40 oz, and the 64 oz beet growler. Extra lids are cheap and make cleaning even easier. I tell all my friends and they are one by one switching as well!

Posted by Ryan on 04/17/2015

5 Star Rating

64oz. Beer Growler

I initially bought a black powder coated 64oz. as my everyday water bottle. I was constantly asked what I think of it (its great, keeps water ice cold all day!) Ended up picking up a 40oz. wide mouth (for water) and another 64oz. to take to the local breweries to fill, as well as a True Pint. I'm completely impressed with their line of products and their warranty policy, not to mention the 5 Percent Back program. I recommend it to anyone looking for a double-walled beverage container.

Posted by Ryan on 04/17/2015

5 Star Rating

32 oz. Wide Mouth

Just picked one up for my Mom. She loves it! Keeps water ice cold all day and just the right size to carry.

Posted by Chris on 04/17/2015

5 Star Rating

16 oz. Pint

This is AWESOME!!!! I had a nice ice cold Pelican Pub beer from start to finish. I put some water with ice cubes in the true pint and even with no lid ice lasted over 8 hours. Really~ so cold it makes your teeth hurt.

Posted by Slick on 04/15/2015

5 Star Rating


This is the only waterbottle i have ever had that keeps ice cubes over 24 hours. AMAZING !!!! LOVE IT

Posted by steve uetrecht on 04/15/2015

5 Star Rating

Hydro Flask Owner

This is my 4th Hydro Flask, gave one away as gift to a friend, ran over one with truck by accident, doesn't leak but is to bent to use, and I keep 2 for my use. I think they are the best cup ever. And lifetime warranty (as long as you don't run over it).....I have had to ask for replacement lids which were sent, no questions. Thanks Hydro Flask

Posted by Theresa on 04/11/2015

5 Star Rating

Buy this please

This is the best bottle ever! I love it.Im rough and throw it around and drop it at my job site and it can take it.I work outside in the hottest hot and coldest cold and this bottle never feels either.To whoever reads this for a review, buy it you'll like it and to the company that made this THANK YOU FOR A GREAT PRODUCT.

Posted by Brack on 04/10/2015

5 Star Rating

True Pint

This pint glass is bomber. I love the feel of the glass. Perfect for drinking on hot days. I can't believe how well it maintains the temperature of the beer you pour into it. Enhances your brew for sure.

Posted by Brack on 04/10/2015

5 Star Rating

64oz is perfect beer vessel

This bad boy keeps your beer cold long after you take it out of the fridge or cooler. Took this bad boy camping and left it out of the cooler most of the afternoon and my beer was still cold. Also no sweating at all. Well at least from the Hydro Flask. Lose the glass growler and pick up one of these.

Posted by alan on 04/10/2015

5 Star Rating

How about for Martinis?

I'll bet it should work really awesome! I have two 40 oz one for hot yoga and the other for the car!

Posted by Mary S on 04/10/2015

5 Star Rating

Awesome product!!!

First water bottle that I didn't have to compromise when I purchased it. It was the perfect volume, I love wide mouths and a really cool color and designs. Thanks Hydro Flask!

Posted by Denita on 04/10/2015

5 Star Rating

LOVE my HydroFlask

I bought my first HyrdoFlask in 2010 and have purchased many many more since! I just returned my beloved Growler after 5 years of keeping my water COLD in the HOT HOT South Florida weather. Warranty replacement was easy, I now have my new Growler. I only wish HyrdoFlask would offer more colors in the 64 oz size.

Posted by Anthony C on 04/09/2015

5 Star Rating

16 oz True Pint for Coffee too!

Picked up a True Pint to add to my Hydroflask family of 5 water bottles. Not for beer but for coffee. And it is just as amazing as the bottles. Now I just need a lid and it would be perfect.

Posted by Tamandal1205 on 04/09/2015

5 Star Rating

The Best!

I recently switched from a competitor's plastic bottle and absolutely LOVE the double-wall insulating properties of the Hydro Flask. The 32oz holds just enough ice water that I can survive the HOT Florida days. I can't wait to take mine camping... Wish I discovered Hydro Flask sooner!

Posted by Katie Brunson on 04/06/2015

5 Star Rating


I seriously wish I could give 100+ stars on this bottle. When I say AMAZING I mean it. DOES NOT LEAK. DOES NOT SWEAT. (we all can say we hate when we have a sweating bottle) I'm seriously in love and have been telling everyone about it. I left it at a friends the other night and I was so upset I left it. I highly recommend getting one. Will be ordering the straw part next!

Posted by Brooke on 04/02/2015

5 Star Rating


What an awesome water bottle! I bought one from my hot yoga studio in hopes of keeping my water cold during the class-- it totally works! I found my self using it ALL the time! I'm a college student and usually carry a water bottle around all the time anyway-- I'll put ice cold water (with half a tray of ice cubes) in it one morning and a night night the ice cubes are still whole and the water is freezing! Only buying this brand of water bottle from now on-- I love it!

Posted by Anne Marie on 04/01/2015

5 Star Rating


I got a brand new one free since the previous one had some odd rust in the bottom... CRAZY AMAZING!

Posted by Thompsie S. on 04/01/2015

5 Star Rating

Out with my Nalgene....IN WITH MY HYDRO FLASK!

I drink approximately 100 oz. of water per day (due to a medical condition). I used to use Nalgene and Camelbak bottles exclusively to carry my water to the office, the gym, etc., but I decided to try the Hydro - it caught my eye at R.E.I. on a display! I had always wanted a sleeker looking bottle that could hold more than 32 oz. but I could never find one! I own the 40 oz. Hydro Flask in blue and now I cannot wait to get a smaller pink one as well! Here is what I adore about the Hydro Flask: DOES NOT LEAK! DOES NOT SWEAT! Sleek design! Thanks so much to the designer of these bottles!!!!

Posted by Kelly E on 03/28/2015

5 Star Rating

The best water bottle ever!

I purchased my hydro flask 3 years ago and fell in love with it the very first day. It goes everywhere with me. I live in Florida and my hydro flask keeps my water ice cold, even on the beach. When I was on a cruise I used my hydro flask to keep my mudslides frosty. It is by far the best water bottle you will ever purchase.

Posted by Joy on 03/28/2015

5 Star Rating

best water bottle ever

I love this water bottle - actually I have two. People thought I was crazy the way I went on and on about the great features of this bottle. Put it in your backpack; doesn't sweat on papers/books/electronics in your backpack. I frequently work outside in remote locations where you have to carry your water with you; after slogging through rough terrain it is so nice to get cold water from my Hydro Flasks instead of the tepid water from previous water bottles I have used. For Christmas last year, I purchased 21 oz Hydro Flask bottles for my entire family. They did kind of look at me strangely when first opening the gift, but since they had the opportunity to use them, the family is telling me how much they use their Hydro Flask bottle and think the bottles are GREAT!

Posted by William C. Herington Jr. on 03/25/2015

5 Star Rating

PERFECT Enough said !!!

If you don't own at least one you should ask yourself WHY NOT. Have gotten several from Dutch Bros. coffee and couldn't ask for anything better. Two great businesses from the state of Oregon.

Posted by Adrienne Woodward on 03/23/2015

5 Star Rating

Awesome product and great customer service to boot!!

I love, love, LOVE this water bottle!! I am a constant iced tea drinker, and the 64oz holds all the tea and ice I need for a 12-hour shift! Did I mention it also keeps the ice solid and my tea ice-cold for the entirety of my shift also?? Excellent! I have a habit of carrying my full jug by the handle, and after about of year of heavy use, the plastic strap that connects the cap to the bottle gave in and broke. I filled out the customer complaint form offering to purchase a new lid, and they shipped a new one to me the next day, free of charge! Not even a few for the shipping! I can't praise this product or company enough... Expensive, but worth every penny! Thank you!

Posted by Mercer on 03/18/2015

5 Star Rating

Best Water Bottle I've Found!

I am always carrying a water bottle. I used to use Nalgene and glass water bottles. I loved the size of the Nalgenes and the cleanliness of glass. This bottle provides the perfect combination of both. It is large enough to avoid having to refill constantly and it does not retain any tastes/smells as plastic does. This water bottle also keeps my water ice cold for several hours. Living in Arizona, water bottles usually heat up fairly quickly which leaves the water undrinkable. I left this water bottle in my car for hours and the water was still cold! Highly recommend!!

Posted by Scott on 03/18/2015

5 Star Rating


I bought myself one of these about a year ago as a birthday gift to myself. I have used it every day since for my morning coffee, and I have absolutely no complaints! I love it so much that I now have a water bottle and a true point on my radar to purchase in the very near future. Hands down the best travel mug I have ever owned!

Posted by Doug on 03/15/2015

5 Star Rating

Great Upgrade

I had been using another rugged water bottle for years and liked it fine but hated the water rings left behind wherever I set it down. After doing more research than I ever thought I would do for a water bottle, I purchased the Hydroflask. Rugged and solid construction with a nice finish. I was a little concerned about not having any splash guard, but to my surprise the shape of the bottle has a way of keeping ice at bay. Great bottle, absolutely recommend!