Birds Stainless Steel Vacuum Flask

4 reviews
$ 39.95 USD

Perfect for long days taking inventory of the museum's taxidermied bird collection or patient vigils waiting for a glimpse of an elusive specimen, this Birds Vacuum Flask will have your drink at just the right temperature whenever you're ready for it. Particularly if you're the type to get lost in your work for hours, it's nice to know that your tea won't have gone cold while you were having a moment of genius.

With a textured design for a unique tactile experience, this flask will keep your drink hot or cold until you're ready to enjoy it.

Volume 18 oz / 500 mL
Width 2.75"
Height 8.75"
Opening Wide mouth
Material High-grade stainless steel
Cap Material High-grade stainless steel, silicone ring
Care Hand wash (do not wash in dishwasher)


Fill it with your favorite mulled hot cider or cold brew, and even if you don't get around to drinking it for hours, you can expect to find your beverage ready and waiting for you at just the right temperature. The metal cap seals tightly, so it won't leak all over your bag. 

Here's how it works: the space between the inner and outer flask wall is evacuated, creating a vacuum (well, a partial vacuum anyway...). In order for heat transfer to take place from the outside world into your cold drink, or from your hot drink to the outside world, it needs nearby molecules to excite. If there aren't many molecules nearby, as is the case in a vacuum, the heat's energy can't easily be passed along, so your drink stays close to the temperature it was when you put it into the flask for a really long time. 

Simply stated, vacuums make great thermal insulation!


Flat Rate $9.95
Orders $75+ ship for free
Expedited service available


Shipping is available to most countries. See details at checkout.

Shipping FAQReturns FAQ

You may also like

Peer Reviews

Customer Reviews
5.0 Based on 4 Reviews
5 ★
4 ★
3 ★
2 ★
1 ★
Customer Photos
Write a Review Ask a Question

Thank you for submitting a review!

Your input is very much appreciated. Share it with your friends so they can enjoy it too!

Filter Reviews:
Rachel P.
United States United States

Wonderful, Beautiful, Sturdy

Amazing product, and good in lots of scenarios--I take it with me daily to class and rehearsal, and it's held up very well in my backpack.

Miriam P.
United States United States


To be honest, I haven't drunk much out of my new flask yet, because I've been keeping it on my desk where I can just look at it. What a work of art! But that's silly, and I fully intend to make a habit of actually drinking from it -- only when I'm ready.

Cognitive Surplus Birds Stainless Steel Vacuum Flask Review
Alicia M.
United States United States

The best water bottle!

Yes, and bought one for my best friend who is also a birder. They’re gorgeous and also keep water incredibly cold. They’re the perfect size, too!

Anja R.
United States United States

Love the thermos

It is gorgeous and keeps things hot. Only thing is i wish it had a sippy lid so that i could drink coffee in the car

Recently viewed