Placeholder Mushrooms Stainless Steel Vacuum Flask / Insulated Travel Thermos – Cognitive Surplus

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Mushrooms 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

If you're leaving home at dawn to spend the day making observations in a misty forest or just enjoy taking your coffee with you wherever you go, this Mushrooms Vacuum Flask has got you covered. Let it inspire you to stay out just a little longer to collect that last bit of important data or fuel your next great idea. 

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.

Infuser Basket Compatible
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
Features Infuser basket compatible
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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Infuser Basket for Stainless Steel Bottles

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Customer Reviews
4.9 Based on 9 Reviews
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United States United States


I am in love with the mushroom pattern on this, and the texture of the bottle is also very high quality! The steel bottle keeps drinks warm for hours and cold for at least 24 hours.

John D.
United States United States

Quality product

Well made and keeps liquids cold!

Elizabeth H.
United States United States


It's a perfect size and keeps my water cold for a very long period of time!

Dhru D.
United States United States

Better than expected!

Love how this bottle looks and it keeps beverages hot or cold for hours. Functional and gorgeous!

L B.
United States United States

Love it!

The thermos works well and the pattern is really cute!

Lauren H.
United States United States

I've Started Drinking...

I have always hated water, and this flask has severely improved my hydration. I love how it looks and am compelled to carry it around with me constantly. It keeps ice cubes cool all day, even with the lid off. I just refill with water and the cubes stay nice and chilly throughout the day. I rarely leave the house (quarantine, yay) but when I do, the lid seals nicely and is easy to spin on and off. Haven't done any warm bevs in it but I might have to... Just been so dependent on it being my water source so haven't gone there! The design is exactly as pictured, with little raised/embossed elements and a semi-rough texture that helps the bottle stay easily grabbable/recognizable due to its distinct tactile feeling. LOVE it. Already bought two more for friends and might just have to keep getting more until everyone I know has their own!

Paula B.
United States United States

Mushroom Flask

I love it! I use it everyday and really like the handle. It makes it easy to carry when your hands are full, heading out the door. Great mushroom design too. Thanks, Cognitive Surplus!

Cognitive Surplus Mushrooms 18 oz Steel Bottle Review
Kateryna B.
United States United States

Love it!

The print quality is amazing, it always makes me happy to look at it and feel it. The flask itself is a very good one: it keeps my drinks cold and warm for a couple of hours no problem. The handle is very easy to hold, especially on my walks. I’ve had a minor issue with the lid, where it takes a couple of tries to screw it on straight, but I don’t mind it too much.

Sammie C.
United States United States


These products are all high quality and perfectly scratch that itch for niche and artistic items. I receive constant compliments and the customer service team is incredible and very quick to fix any issues!

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