NEW FOR 2017! The original capCAP is one of the most popular water bottle accessories of all time, and its unique 2-in-1 design has fans all over the world. For the new version, we went back to the drawing board to see how we could make the capCAP even better, and we came up with some pretty neat features. For starters, we redesigned the cap-bottle interface so that the capCAP is now compatible with popular stainless steel water bottles from manufacturers like HydroFlask, Klean Kanteen, and Fifty/Fifty. Other new features include rubberized grips on both the small and large caps and a "Cap Keeper" notch on the strap that holds the small cap out of the way when drinking.

As always, the capCAP is 100% BPA-free, polycarbonate-free, and phthalate-free, and both caps are made with FDA-approved, food-safe polypropylene (#5) plastic.

*Note: The new capCAP is only available in limited quantities until 2017, when it will be available widely in stores and online. If you’d like to order the old capCAP instead, please let us know via email. Although, honestly, we don’t really see why you’d want to, since the new version is better in just about every way…

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The water bottle cap for humans.



capCAP is the civilized 2-in-1 accessory cap for Nalgene, CamelBak, and other popular wide-mouth drink bottles.

Most wide-mouth bottles are easy to fill and clean, but the standard opening is too big to drink from without spilling. Narrow-mouth bottles are great to drink from but you can forget about putting ice cubes in them, let alone cleaning them. And bottle inserts don't really fix a spout that was never meant for daily drinking.

capCAP offers the best of both worlds. Drink spill-free through the small spout, and then clean and fill easily with the large cap. The rubberized small cap (available in green, blue, or black) is easy to grip, even with gloves on. Don't forget that the wide, rounded strap is more comfortable to hold too.

capCAP is 100% BPA-free, polycarbonate-free, and phthalate-free. Both caps are made with FDA-approved, food-safe polypropylene (#5) plastic. It is also covered by our lifetime warranty.



Green / Gray
Blue / Gray
Black / Gray

Opening Size: 2.5" (63mm)

Dry Weight: 1.4 oz. (39.7g)

Cleaning: Dishwasher-safe (top rack only)




What water bottles are capCAPs compatible with?
capCAP works with most popular BPA-free wide-mouth bottles. If you refer to the capCAP compatibility information below (in the compatibility section), you will find more specific information on compatibility. Please note that there are too many bottles on the market for us to know all of the ones that are compatible. So if you discover a new compatible bottle, please let us know. We will add it to the site.

Why does leaking occur between my water bottle and the capCAP?
If leaking occurs, you are likely using a water bottle that is not compatible with the capCAP. Please refer to the capCAP compatibility information below.

What are the thread dimensions of the top cap?
The smaller cap (or top cap) is non-standard and was designed to work solely with the capCAP.

What can I do to make the fit on my capCAP not so tight?
Some time ago Nalgene and CamelBak switched to a new material for their clear, colored water bottles. These bottles are marked as "Everyday" (on the Nalgene bottles) and "BPA-free" (on CamelBak bottles). humangear has already adjusted the fit of our capCAP so that it now works properly on these new bottles, as well as all the previous bottles. However, a small number of capCAPs were sold when we first introduced the product in 2008 that may have a tight fit with the updated bottles. If you happen to have one of these original capCAPs and find it difficult to screw the bottom cap onto your bottle, please email us at Please include your name and mailing address, and we will send you a replacement large (bottom) cap, free of charge. We offer this replacement in the spirit of the lifetime warranty that comes with all of our products.

Where's the most interesting place that humangear has had a meeting?
There have been some pretty epic meeting locations, but we'll have to go with the inside of a Toyota Chinook overlooking San Francisco from the vista point at Twin Peaks.

What are the care and cleaning instructions for the capCAP?
The capCAP should be washed before first use. To clean, hand wash in warm soapy water. If your capCAP begins to have an odor, we have a number of other suggestions including soaking it in warm water with lemon; soaking it in warm water with baking soda; washing it in a dishwasher away from the heating element (be sure to remove the strap first as the strap isn't dishwasher safe) or follow some of the recommendations for cleaning Nalgene bottles.




capCAP works with most popular BPA-free 63mm wide-mouth bottles including:

Nalgene 1L: HDPE, Tritan, PC

Nalgene SS

Guyot SS

Nalgene OTG: Everyday, Tritan, PC

All CamelBak Better Bottles

Cyclone (PC)

The capCAP is not guaranteed to work with Klean Kanteen wide mouth bottles; capCAPs may work on some Klean Kanteen bottles and may leak on others. We've received mixed reports on the compatibility of the capCAP with the HydroFlask Wide Mouth 40 oz. Insulated Stainless Steel Bottle. capCAP is not compatible with the 16 oz. Nalgene bottle.