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  • Keeps your drink colder even longer
  • Unique internal valve eliminates whistling sounds
  • Easy to drink from and allows for 1-handed open and close
  • Designed to fit 12, 18, 21 and 24 fl. oz. standard-mouth Hydro Flask bottles
  • Made from BPA-free polypropylene #5


View all Hydro Flask Water Bottle Accessories

REI membership


Best Use Multisport
Material(s) Polypropylene
Dimensions 2.7 x 2.7 inches
Weight 1.4 ounces
Rated 3 out of 5 by from It's ok. My hot beverage stays hot, even when the spout is open for at least a few hours. I've been sipping on a bottle full of coffee for the last couple hours, and it's still hot (this is my first use). What I don't like about the sport cap is that you have to be careful not to tip the bottle back quickly, as the air vent is right next to the spout (to allow liquid to flow out). Tipping it back too quickly will cause you to spill on yourself. I don't know why they didn't put the air vent on the opposite side of the nozzle. You may still spill on yourself, but at least that's further away from where you tip back your liquid. I think I'm going to return it, and see if they have one with a straw.
Date published: 2015-09-06
Rated 2 out of 5 by from Great until the valve cover gets lost This is good way to improve an old bottle, Unfortunately me kids keep losing the small transparent rubber covers for the air vent and the bottles are no longer useful. We promptly received warranty replacements for 3 sport caps, but now have 5 out of 6 without air vent covers. I would love to buy a couple dozen of these little covers so we can keep replacing them every few weeks. But otherwise, these aren't useful anymore. For adults who can be careful with the caps, they might work great. But I don't recommend them for kids.
Date published: 2015-11-28
Rated 2 out of 5 by from Love Hydroflask.... but, hate new sports cap! I purchased 3 new sports caps to replace existing older caps with a 'spout'. I love the design and new spout, but HATE the fact that the tiny rubber piece came right off the first time we used the new cap. The new rubber piece is smaller than the previous rubber pieces on the older caps. Any tips on how to NOT have these tiny rubber pieces come off?
Date published: 2015-09-29
Rated 2 out of 5 by from Cool accessory, except... If you aren't careful the microscopic clear rubber airlock can pop out, rendering the cap useless (unless you want to be sprayed in the eyes with water with every sip). I cannot recommend this product until that feature is improved. Sorry guys, my first let down from hydro flask.
Date published: 2016-02-07
Rated 1 out of 5 by from leaks everywhere! I love the feel of this one over the Klean Kanteen sipper with it's larger loop. It's easier to carry. BUT this style leaks terribly. It's very hard to get it completely closed so every time my children's water bottles lay down in a bag or in the car they spill everywhere. Also, the little silicone air valve falls out at the slightest touch. :( I really wish they would fix these two things. Thankfully the waterbottle sport tops easily fit other brands.
Date published: 2016-05-18
Rated 1 out of 5 by from Poorly designed with major flaw We bought 3 of these to four our 3 children so they would have an easier time drinking and hopefully not spill. The product looks like it should do the job and for the most part it does except for one design flaw. There is a little valve that you can't see in the product photo hidden behind the plastic loop. This valve lets air pass through while you are drinking, however the tiny silicone stopper can come out pretty easily. Especially if you have a curious 5 or 8 year old that touches it with their finger. The plug then comes out and due to the design is physically impossible to get back in. Therefore you are left with a leaking flask. The stopper is about a 1/4" in size with a 1/2mm pin hole you need to pass it through. And you have to try to shove it in 1.25" cylinder which is impossible. I tried repairing it with tweezers but couldn't even reach the other end. Don't purchase for kids and there is risk for adults. Once the plug comes out the flask will leak.
Date published: 2015-09-05
Rated 3 out of 5 by from Works great until it doesn't Works great until the little plug falls out when you're washing it, now it just leaks.
Date published: 2015-09-10
Rated 3 out of 5 by from Leaks :( Iv had this sports top for awhile now, and other than the fact that it leaks if you hold it upside down, which is frustrating because I can't just throw it in my bag w/o the fear of it leaking all over my things. Other than that I love my hydroflasks to death! Just not this top.
Date published: 2016-02-20
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Will this fit the 18 fl oz bottle?????

Asked by: Phil the sailor
The Standard Mouth Sports Cap will not fit the 18 Hydro Flask bottles.
Answered by: REIservice
Date published: 2017-01-25

will this fit 32 oz hydroflask

Asked by: patricia p
​This cap does not fit any 32 ounce Hydro Flask bottles.
Answered by: REIservice
Date published: 2017-03-29

It seems as though there is a repeated qualm with this lid--that it leaks anytime it's not up right. Has this been improved at all? I'm purchasing a hyrdoflask for my sis, but she's extremely athletic, so I would love to be able to buy her this lid too!

Asked by: cclomen
This cap has a rubber gasket located on the underside of the rim. We have only heard of leakage issues when this gasket has been removed.
Answered by: REIservice
Date published: 2017-01-27

Description states "Removal spout for easy cleaning". How do you remove the spout?

Asked by: kate22ca
The spout is not removable. Thank you for calling this to our attention, we will have our website updated shortly.
Answered by: REIservice
Date published: 2017-05-26

Will this top fit the STANDARD 24 oz Hydro Flask bottle?

Asked by: LDS
The Standard Mouth Sports Cap will fit the standard 24 ounce Hydro Flask bottle.
Answered by: REIservice
Date published: 2016-12-16

Will this fit a hydro flask 24 ounce narrow mouth?

Asked by: richardeee
The Standard Mouth Sports Cap will not fit the 24 ounce narrow mouth Hydro Flask bottles.
Answered by: REIservice
Date published: 2017-02-08

Will this fit Subzero water bottles?

Asked by: Squatchy
REI does not stock SubZero brand water bottle so we are unable to test the compatibility of this lid to that bottle. You are welcome to contact Subzero to ask if the Hydroflask lid is compatible.
Answered by: REIservice
Date published: 2016-05-13
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