The Eco Vessel Stainless Steel Insulated Sippy with NUK Spout claims to be easy to drink, easy to hold, easy to clean, and has the ability to keep contents cold for hours. This insulated sippy is made with two layers of vacuum sealed food grade stainless steel. It contains no BPA, phthalates, or liner. The cup only has a few parts; they include an integrated handle and neck that accommodates a ring, and NUK spout. It is a simple cup that comes in a few different colors as well as natural steel. This cup weighs about 1 pound, and is widely available online.
A variety of Toddler Sippy Cups
Credit: Micah James
There was a lot to like about this cup. We liked that it was made primarily of stainless steel. We also liked that it was insulated, and easily kept drinks colder for longer. This cup scored well in both eco-health, and ease of cleaning, which was a rare combination in our tests. The simple limited piece design was also a nice touch, and made this cup easy to clean, requiring no special tools except perhaps a standard bottle brush.
This cup did very well for leaks. Like the other Nuk spout cups in our test, this cup earned a 10 out 10 for leaks, and proved that it had what it takes to be called leak-proof. Putting the great eco health and leakage scores together, and you have a cup we really liked, but should have loved. As a matter of fact, this cup scored great in every metric but ease of use.
The NUK spout was the most difficult to drink from spout/valve in our tests
Credit: Micah James
There wasn't much to dislike about this cup. It really scored well in all metrics but one. Unfortunately, it scored so low for ease of use, it knocked it straight down to the second half of the cup rankings.
This cup was just as hard to drink from as the other NUK Spout cup we tested. The ease of sucking was the worst out of the cups we tested, meaning it was the hardest cup in our tests to drink from. Even when we tried to use more of a suckling motion it still didn't work great. We almost had to bite the spout to get liquid to come out, and even if we did get some out, it wasn't a consistent flow rate. This meant the cup also might contribute to oral hygiene problems depending on the type of liquid it holds. Given the American Dental Associations recommendation that toddlers use valve free cups to avoid excessive sucking, this cup required more sucking than just about any other cup we tested, so it failed to earn points for this health consideration.
This cup was also heavy, weighing in at a whole pound, it was the heaviest cup
This cup was heavier than the other cups in our tests
Credit: BabyGearLab Staff
in our tests. Sure we expect stainless steel to be heavier than plastic, and insulated stainless to be heavier than non-insulated, but this cup was heavier than the two Thermos cups we tested, which were both insulated steel cups.
This cup was more difficult to grip than other cups we tested. While it had handles on it, the handles were fairly small and close to the cup body, it was a little difficult for some toddler users to get there hands in the holes and to adjust the cup properly to drink from the spout at just the right angle. While handles seemed to help most cups, and are certainly nice on a cup this heavy, they just weren't done well, and we think the cup would have been better off without them, or with a bigger grippier option.
While this cup had many of the attributes we revere in a sippy cup, like being leak free and eco-healthy, it failed in the ease of use category. As a matter of fact, it scored lower for ease of use in our tests than any other cup. The difficulty sucking, combined with the heavy weight and almost useless handles, meant this cup was one that just didn't get used. So no matter how awesome its other attributes, we doubt toddlers will make this a cup of choice. Therefore, this is not a cup we recommend.
Above are photos of both the Thermos Foogo Phase 3 Insulated (left), and the Eco Vessel Insulated Sippy (right)
If you are looking for a good stainless steel insulated cup, our Top Pick for Insulated, the Thermos Foogo Phase 3 Insulated
was a great cup. It was easy to drink from, easy to clean, and cheaper than the Eco Vessel Insulated Sippy.