Placeholder Equations that Changed the World Travel Mug | Cognitive Surplus

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Equations that Changed the World 18 oz Steel Bottle

$ 39.95
9 reviews
Item is in stock Only 0 left in stock Item is out of stock Item is unavailable

Rather than looking up part-way through your proof to find – once again – that your coffee has gone cold, pour that precious brew into your fancy new math flask, and never have room temperature coffee again! Let yourself get lost in the elegance of your work and the beauty of the equations both on your page and on your flask. Wrapping around this brick-red bottle, you'll find some of the most important, groundbreaking equations our world has known. Now go ahead and add your equation to the list.

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.

Hand-wash only
Carbon Neutral Shipping & Operations
Compostable Packaging

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!

Volume 18 oz | 530 mL
Width 2.75"
Height 8.75"
Opening Wide mouth
Material High-grade stainless steel
Origin Designed in Oregon, Built responsibly overseas
Cap Material High-grade stainless steel, silicone ring
Care Hand wash only

Flat Rate $7.95
Orders $40+ ship for free
Expedited service available


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

If you're shipping to Europe, Asia, the Middle East, or Oceania, please check out our European website for lower shipping rates and quicker delivery times.

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within 30 days of purchase

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On USA orders over $75

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Customer Reviews
4.9 Based on 9 Reviews
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Filter Reviews:
Aleksandra G.
United States United States


Love my new water bottle

A Cognitive Surplus Customer
United States United States

Great quality, real math!

Bought "Equations that Changed the World 18 oz Steel Bottle" as a gift for my husband, a math major. He loves it! Not only is he impressed with the quality of the flask, but he is also impressed with the math on the outside. He said lots of times gifts like this are too generic, but with this one he feels like they definitely consulted with a mathematician to create this.

Jessica B.
United States United States


Beautiful to look at; lovely to use. Keeps water cold all day long. Excellent construction. Came back to buy another one! Well worth the money.

Joanne C.
United States United States

almost there!

Steel Travel mug: 1) The raised print on the "Equations that Changed the World" is fantastic. I really enjoy that tactile element on this beverage container. 2) opening and closing the top has gotten tricky. There is significant friction between the threads as metal rubs on metal when screwing on the top. 3) I am very pleased with the bottle's ability to retain heat. 4) love the handle!


Equations that Changed the World Stainless Steel Vacuum Flask

Bought this for a friends birthday gift. It was wrapped great and arrived in time. Will definitely buy from this shop again.

Kathy P.
United States United States

Just got it and already want another!

Awesome thermos! Feels and looks like great quality. The textured feel adds to an already really cool design. I'm already wanting to buy another and I just received this one in the mail today!

Begona B.
United States United States

Very Pleased with Purchase!

I bought this flask as a Christmas present for my son, BUT NOW I WANT TO KEEP IT!! This is NOT a smooth flask! All the pictures and formulas are textured! I just LOVE this flask! I will definitely be purchasing one for myself soon.


Equations that Changed the World Stainless Steel Vacuum Flask

It’s totally perfect. Arrived quickly, very high quality, love the design!

Amy E.

Equations that Changed the World Stainless Steel Vacuum Flask

Super fast shipping. The water bottle is so high quality - I’m very impressed! Would definitely buy from here again.

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