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Hydro Flask Standard-Mouth Vacuum Bottle - 21 fl. oz.


    Hydro Flask Standard-Mouth Vacuum Bottle - 21 fl. oz.

    The 21 fl. oz. Hydro Flask Standard-Mouth vacuum bottle is ideal for keeping fluids hot or cold during weekend bike rides and hikes. See details

    • $25.95

    Item # 850807

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    The 21 fl. oz. Hydro Flask Standard-Mouth vacuum bottle is ideal for keeping fluids hot or cold during weekend bike rides and hikes.

    Product size and color

    The 21 fl. oz. Hydro Flask Standard-Mouth vacuum bottle is ideal for keeping fluids hot or cold during weekend bike rides and hikes.

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    The 21 fl. oz. Hydro Flask Standard-Mouth vacuum bottle is ideal for keeping fluids hot or cold during weekend bike rides and hikes.

    • Double-wall vacuum insulation keeps the contents hot for 12 hrs. and cold for 24 hrs. so you can warm up with cocoa or cool down with your favorite cold beverage
    • The inside temperature won't affect the outside temperature of the container—that means no burned fingers from hot beverages or condensation from ice-cold drinks
    • Standard-mouth opening is 1.81 in. in diameter, making it easy to fill the bottle with coffee, tea or sports drinks
    • Tough, food-grade 18/8 stainless steel is BPA free and resistant to bacteria and odors
    • Bottle fits in most car, bike and stroller cup holders and water bottle cages
    • Please note: Hydro Flask cannot guarantee against leaks when the bottle is filled with carbonated beverages; keep the bottle upright


    Item 850807

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    Hydro Flask Standard-Mouth Vacuum Bottle - 21 fl. oz. Specs
    Best use
    0.6 liter
    21 fluid ounces
    2.9 x 10.6 inches
    Stainless steel
    Stainless steel
    Screw cap
    10.4 ounces
    Liquid capacity (L)
    Liquid capacity (fl. oz.)
    Fits in cup holder
    Water bottle material
    BPA free
    Bottle opening
    Water bottle cap type

    Hydro Flask Standard-Mouth Vacuum Bottle - 21 fl. oz.

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    Hydro Flask Standard-Mouth Vacuum Bottle - 21 fl. rated4.6667out of5by24.
    Rated4out of5byfromSolid, does its jobNeeded an extra bottle for my Miir bottles, and this suited the bill.
    Date published: 2014-01-30
    Rated5out of5byfromGood heat retentionOn a recent project, I measured the heat loss on various size stainless steel insulated containers (Thermos bottles, coffee cups, etc.). I started by filling each container to its capacity with 200 degree water. Below are the temperatures for containers in the 16-24 oz. range after a 3 hour & 10 hour period - numbers shown after the item are: temp. after 3 hrs and temp. after 10 hrs. The list includes this item as well as the others listed. I also included a pretty much standard (larger size) 32 oz. Thermos bottle and a "no-name" 16 oz. insulated container with sealing cap & cup/lid that I got free for subscribing to a magazine for comparison. Items are listed in order of the content temperature after 10 hours. 32 oz Thermos 193,178 24 oz Thermos Direct Drink 180, 152 16 oz Thermos Backpack bottle 177, 143 16 oz No-Name publication give-away bottle 178, 142 21 oz Hydro Flask 177, 139 16 oz Thermos Cup rotating seal 169, 130 20 oz Kleen Kanteen 167, 125 24 oz Oxo Good Grips LiquiSeal 150, 104 16 oz Kleen Kanteen 151, 103 16 oz Starbucks Cup 144, 100 Over time, heat loss occurs through the double stainless walls with a vacuum between them. However, most heat escapes due to poor design, location, and sealing of the lid and/or stopper. Specifically the lid or stopper should seal at or below the upper end of the double wall vacuum section of the stainless portion of the container and the lid/stopper should have some kind of insulation itself, if only an internal air space. For instance the stainless steel Starbucks cup itself has pretty good insulation qualities on its own and the lid seals just at the upper end of the double wall vacuum section. But the cap is a single piece of plastic that just bleeds heat off the surface of the liquid inside. The Oxo is even worse in that it has the same lid configuration the Starbucks cup has but in addition has a band of about an inch between where the lid seals and where the vacuum insulation starts – BIG heat loss here.
    Date published: 2014-01-25
    Rated5out of5byfromgreat temperature retentionhesitated due to the cost, but really like the bottle. keeps water cold for hours.
    Date published: 2014-01-23
    Rated5out of5byfromBest of the bestBest there is. The great thing about this design is that you get the feel of its durability while also having a stylish, subtle look. It doesn't get any better than this.
    Date published: 2014-01-04
    Rated5out of5byfromWorks Great!I used this on a trip to the beach in South Carolina. Worked great. Filled with ice in the morning and provided cold water all day. Very strong.
    Date published: 2013-12-30
    Rated5out of5byfromWorth the CostIf I fill up with ice on Friday there is still some ice on Sunday. Perfect for traveling. Once I get through security at the airport I fill up and am confident it won't spill in my bag.
    Date published: 2013-12-24
    Rated5out of5byfromGreat Bottle, does what it claimsPurchased this bottle while I visiting family in Bend, OR on a road trip. I kept seeing the little man with the "squiggly hair" on bottles people were carrying around town. I figured these folks new something about a good water bottle. I wasn't disappointed. Headed to REI to pick up a special edition they sold benefitting COTA. The bottle felt great, and the sales person told me he had one and it was his favorite bottle. I used to use another brand I really liked, but now this is my favorite water bottle. Insulated and perfect to hold. Left it in the car with 100+ degree temp, and a few hours later when we came back to the car, the water was still ice cold. Awesome! It sat out overnight, and was still cold the next day in the heat. Can't speak highly enough of this product. I'm sold!
    Date published: 2013-12-17
    Rated4out of5byfromGood BuyI use this everyday for work and play. Keeps cold temps overnight. As for hot temps, not very good. At least not for coffee.
    Date published: 2013-11-21

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